Category Archives: Football and Science
How coaching can benefit from performance analysis
Generally, performance analysis can be classified into two main categories: notational analysis and motion analysis. The two systems have different focuses. Notational analysis provides factual record about the position of the ball, the players involved, the action concerned, the time and the outcome of the activity, etc. Motion analysis focuses on raw features of an individual’s activity and movement, for example, identifying fatigue and measuring of work rate. For further details about motion analysis, please refer to my previous post. The two systems contribute for the performance analysis which has three main aims:
- Observing one’s own team’s performance to identify strengths and weakness
- Analysing opposition performance by using data and trying to counter opposing strengths and exploit weaknesses
- To evaluate whether a training programme has been effective in improving match performance
Performance analysis is not just about analysing matches and games. It is essential in the training programme to help coaches improve players’ performance. The following figure shows the coaching cycle.
Figure 1. The coaching cycle
Performance analysis plays a key role in this cycle. Starting from the top, “Performance” means the performance in the game or training. “Observation” can be from the coach or video camera. Since research indicates that coaches are able to recall fewer than half of the key incidents that arise during the game, video camera is a better way which can record all the key events (actions and movements) for further analysis. In “Analysis”, it means analysis of data which include data management. For example, using performance analysis software to code the game, editing footages from the camera, extraction of data from data provider, etc. These are the areas in which the performance analyst spent most of the time. The product of this “analysis” stage can be statistical analysis and video recordings. In “Interpretation”, it can be put in two ways according to my experience. It could be done by coach or performance analyst. Some analysts have the authorisation from coach to interpret the data and then write a report or make a presentation to the coach or team. Some coaches just want the data from performance analysts and the coaches will interpret the data by themselves. It really depends on the coaches’ preference and the partnership between the analyst and the coach. After that, “planning” means the coach plan what to do after knowing what went wrong or which part the team did well. The coaches have to evaluate the performance prior to this planning stage. Otherwise, he doesn’t know how to improve the team’s performance in the next match. In most of the cases, it means the planning of the coaching session using the result of the performance analysis. “Preparation” means the execution of those coaching session in the training so prepare the team for the coming game. It will go back to the “Performance” stage and the whole cycle keep going.
In my opinion, performance analysis plays a key role in three stages in this cycle: “observation”, “analysis” and “interpretation”.
Reference
CARLING, C. et al., 2005. Handbook of Soccer Match Analysis. Oxon: Routledge
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What is “Zone 14” in football?
Through the introduction of football performance analysis, football games has been analysed in many ways. Zone 14 was classified as the “golden square” in the pitch which helps teams score more goals. It was supported by evidences showing that successful teams had a better performance in zone 14. In this post, the two examples used would be France (1998-2000) and Manchester United (1998-1999).
Where is Zone 14?
By dividing the field into a six-by-three grid, there are 18 zones on the pitch. Zone 14 is the zone located in the middle of the pitch immediately outside the penalty area appears crucial for goal scoring (Taylor et al., 2002). It is shown in the following diagram.
The location of Zone 14 (Grant et al., 1998)
Why is Zone 14 so important?
It is one of the key factors to differentiate the successful and unsuccessful teams (Grant et al., 1998). Other researchers had the same result showing that successful teams attack through the centre of the field more effectively than less successful teams (Grant, 2000; Horn and Williams, 2002).
Generally, there are 4 key points that successful teams were found to play in Zone 14:
- More passes to all zones to the side and ahead of zone 14 (Horn et al., 2002)
- More forward passes from and within zone 14 (Horn et al., 2002)
- To make more passes in zone 14 compared with unsuccessful teams (Grant et al., 1998)
- To generate attempts on goal from possession regained in zone 14 (Horn et al., 2002)
The first example is France national team (1998-2000). In July 2000, France became the first nation to win the European Championship (2000) as World Champions (1998).
France National Team in Euro 2000 (BBC Sport, 2012)
It was found that 81.3% of their assists in two competitions came from the central area (Horn et al., 2000). In other words, France’s attacking play was narrow. Another finding showed that the majority of France’s attempt at goal came from assists in central attacking area just outside the penalty area (Horn et al., 2000).
The second example is Manchester United FC (1998-99), which was the first English side to win Premiership, F.A. Cup and European Champions League in the same season.
Manchester United 1999 (Sawh, 2010)
Grant and Williams (1999) did a research on this team and found that passing was the most common form of assist. Moreover, the majority of passing assists came from central attacking area.
What is Zone 14?
The above findings gave a brief idea what zone 14 is. Different researches have their own view but generally their opinions were very similar. Grant et al. (1998) argued that Zone 14 is the attacking midfielder area which is the crucial area for producing successful attack. Horn et al. (2000) and Taylor et al. (2002) both argued that Zone 14 is the key area which produces vast majority of passing assist. Grant and Williams (1999) did not mention zone 14 but they found that passing is the most common form of assist and the majority of passing assists came from central attacking area. In fact, some coaches know the importance of this zone but they refer it by using another name “The Hole”. However, from the perspective of performance analysis, the researchers had brought forward the understanding of how it works (Telegraph, 2002), which is shown in the following paragraph.
How to use Zone 14 effectively?
Effective use of Zone 14 must be combined with positive, forward passing and tight possession from the back of the field (Telegraph, 2002). The keywords are “positive, forward passing” which lead to the next question “where the ball should be passed?” According to the Horn et al. (2002), teams were more than 4 times more likely to score goals by playing directly into the penalty area than playing laterally to the wings. In other words, fewer goals would be scored through possession leaving zone 14 to the wide areas. Possession time is another reason why the ball leaving zone 14 should be passed into the penalty area directly. Horn et al. (2002) found that the ball was kept in zone 14 for 2.7 seconds in average in order to score a goal. If the possession lasts over 8 seconds, then it won’t produce an attempt on goal. That means quick attack is a key point in using zone 14. No doubt, moving the ball laterally rather than forward into the penalty area is likely to introduce more passes and longer time in possession, then the threat of zone 14 would be neutralised.
Who is Zone 14 for?
The zone 14 is effective only when exploited by a skilful player who can quickly change the direction of attack with a short pass or twisting run lasting no more than 8 seconds (Horn et al., 2002). Therefore, the players with the ability to play in zone 14 are highly technical. They should be the players that were regarded as the most exciting to watch. Grant et al. (1998) mentioned Zidane and Bergkamp as examples.
Zinedine Zidane (Rascojet, 2011)
Here is an example showing Zidane’s play in Zone 14:
Dennis Bergkamp (The FA, 2013)
Here is an example showing Bergkamp’s play in Zone 14:
Balance
Although Zone 14 is so important in attacking, it doesn’t mean that teams should not make crossing from both flanks. Crossing is a very effective way to produce goals also. In fact, Grant (2000) found that successful teams are effective at using crosses to score goals. The key point is that teams should avoid using zone 14 to attack wide areas, which is proved in previous findings. Instead of using short wide passes from zone 14, teams should switch the ball across the whole field, or move the ball forward all the way down one side to attack flanks and make crossing (Horn et al., 2002). In the example of Manchester United (1998-99), it was found that the team was able to make flank attack and have the ability to penetrate through central attacking area (Grant and Williams, 1999). In the France team (1998-2000), their attacking play was very narrow so there were not many crossing assists.
Conclusion
Zone 14 is located outside the penalty area. It is a factor to differentiate successful and unsuccessful teams because it provides most assist. The most effective way to use zone 14 is to make a forward passing into the penalty area. Moreover, the attacking play should be quick. The possession in zone 14 should not be more than 8 seconds. The importance of flanks attack should not be ignored because a successful team should be able to make both attacking styles.
In my opinion, the best way is to attack through zone 14 first as it is more effective. If they can’t penetrate through the central attacking area, then they attack the wide areas.
References
BBC Sport, 2012. Euro 2000: The French Revolution [digital image] [viewed 17 August 2013]. Available from: http://news.bbcimg.co.uk/media/images/60195000/jpg/_60195604_81575581.jpg
GRANT, A. & WILLIAMS, M., 1999. Analysis of the Final 20 matches played by Manchester United in the 1998-99 season. Insight, 1(3), 42-44
GRANT, A., 2000. Ten Key Characteristics of Successful Team Performance. Insight, 3(4), 26-27
GRANT, A., T. REILLY, M. WILLIAMS & A. BORRIE, 1998b. Analysis of the Successful and Unsuccessful Teams in the 1998 World Cup. Insight, 2(1), 21-23
HORN, R. & M. WILLIAMS, 2002. A Look Ahead to World Cup 2002: What Do the Last 40 Years Tell Us? Insight, 5(2), 26-29
HORN, R., M. WILLIAMS & A. GRANT, 2000. Analysis of France in World Cup 1998 and Euro 2000. Insight, 4, 40-43
HORN, R., WILLIAMS, M., & ENSUM, J., 2002. Attacking in Central Areas: A Preliminary Analysis of Attacking Play in the 2001/2002 F.A. Premiership Season. Insight, 5(3), 31-34
Rascojet, 2011. Zidane [digital image] [viewed 17 August 2013]. Available from: http://www.rascojet.com/blog/wp-content/uploads/2011/01/Zidane.jpg
Sawh, M., 2010. manchester_united_1999 [digital image] [viewed 17 August 2013]. Available from: http://sackthemanager.files.wordpress.com/2012/01/manchester_united_1999_cham.jpg
TAYLOR, S., J. ENSUM & M. WILLIAMS, 2002. A Quantitative Analysis of Goals Scored. Insight, 5(4), 28-31
The FA, 2013. dennis-bergkamp-testimonial [digital image][viewed 17 August 2013]. Available from: http://www.thefa.com/~/media/Images/TheFAPortal/News%20Articles/2013/dennis-bergkamp-testimonial.ashx?w=620&h=349&c=facupgallery&as=1
THE TELEGRAPH, 2002. Scientists find football’s golden square [online]. Available from: http://www.telegraph.co.uk/sport/football/3028353/Scientists-find-footballs-golden-square.html
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‘Why foreign players migrate and the effect their involvement has had on English football since the inception of the Premier League’ (Part 3)
In parts 3, 3a and 3b of this blog we come to analysing the major different views and perceptions on the issue: the three that frequently appear include the notions that foreign players are having a seriously detrimental effect on the production, development, and opportunities available to indigenous talent: which is therefore having a negative effect on the performance and development of the national side (Maguire & Pearton, 2000). Finally, the migratory patterns that resonate towards the core of football have heralded a process of systematic ‘deskilling’ of ‘donor’ clubs, leagues, and nations such as Africa. These sentiments are strongly held in England, but are also echoed in other countries such as Italy, as former Italian U21 coach Cesare Maldini (2000) states:
“At youth level, our football is getting worse. We don’t have the players any more. The increasing number of foreigners in our game means the opportunities for the youngsters are vanishing”
However, if we refer to recent research therein lays a controversial alternative story for the former arguments. Solberg and Haugen’s (2008) research offers a useful insight behind the phenomenon of foreign player migration in football. The authors conclude in their research that despite the view point of the common English football fan and some senior figures in world football the migration of foreign players is actually having a beneficial effect on the development of indigenous players as opposed to a detrimental effect. Further advocates of this theory (Akindes et al., (2007) provide us with evidence that when African players migrate to Europe they gain further knowledge and ‘European’ football traits, thus developing them as players and individuals.
Although, this is also a two-way process whereby at the foreign players exchange their knowledge and ‘African’ footballing traits with the indigenous players, which creates a positive learning environment for both parties. Furthermore, Elliott and Weedon (2010) support these conclusions with their own branch of research, which concerned itself with players from the English Premier Academy League. Their evidence provided additional reinforcement for Solberg and Haugen’s findings and delivers a strong basis to argue that a process of ‘feet-exchange’ rather than ‘feet-drain’ – a term which is derived from the ‘brain-drain’ early work in the 1960’s which examined the issues that ‘donor’ nations face when a highly skilled workforce migrate or relocates (Iredale & Appleyard, 2001) – is actually occurring within the Premier Academy level.
‘Feet-exchange’ is a two-way process whereby foreign and indigenous players exchange their skills, technique and knowledge, and it offers a strong counter argument against the common views and negative perspectives, at least within the Premier Academy League level. In England the game is known for its pace and physicality (Elliott & Weedon, 2010), however, English players are seen as technically inferior to their European counterparts. Within Elliott and Weedon’s paper they include their qualitative based evidence in the form of interviews with various academy coaches and managers from the across the English Premier Academy clubs. One academy manager states that in his opinion:
“[Foreign players] are far more technically oriented . . . Technique is so important, it’s the great English drawback. Physically we’re good, tactically we’re okay, but technically we’re poor. The Dutch and the Italians totally leave us standing. The [foreign] boys we’ve got, their technique is really, really good, and there’s the challenge for the English boys, they’ve learnt that they have to work on their technique.” (Anon, 2010).
As previously mentioned, the English game is known for its pace and physicality, and herein lies the two-way process of ‘feet-exchange’: as foreign players must adapt and learn to deal with the physicality and pace of the English game – with the aid and exchange of knowledge, sometimes achieved purely through the observation of the indigenous players – and therefore the indigenous players also learn to hone and improve their technical skills by playing with far superior technical players (Elliott & Weedon, 2010). This transfer of skills is concluded by an academy coach in Elliott & Weedon’s paper, who states that foreign players ‘raise the bar’ for the indigenous players. Taylor (2007) further adds that:
“[Foreign players] brought in training [philosophies] and lifestyle ideas that are ahead of our own. They have broken down prejudice and national stereotypes. As a group, they have set standards of attitude and behaviour that have been as good for our society as they have been for our game.”
In summary the current research in particular that carried out by Elliott and Weedon (2010) has contributed to the dispersal of the popular discourse that foreign players are stifling indigenous players’ opportunities to play and develop, at least within the English Premier Academy League. Further research needs to be conducted to conclude whether the influx of foreign players is preventing the indigenous players from graduating into the first teams or is it that we as a footballing nation are just not producing players good enough to challenge the foreign imports.
Part 3a of this blog will naturally follow on from Part 3 with the perceived negative effects that the influx of foreign player migration has had on the performances and development of the England national team. To offer evidence for or against these claims I will analyse the performances of the national team over the past three decades, the latter of which heralded the influx of the foreign player migration trend.
References:
Andreff, W. (2009). The economic effect of ‘Muscle-Drain’ in sport. In: Walters G and Rossi G (eds) Labour Market Migration in European Football: Key Issues and Challenges. London: Birkbeck Sports Business Centre, pp. 9–31.
Anon. (2010). In Elliott and Weedon’s (2010). Foreign players in the premier academy league: ‘Feet-drain’ or ‘feet-exchange’? International Review for the Sociology of Sport 46(1): 61–75.
Blatter, S. (2003). In Darby, P., G. Akindes, and M. Kirwin (2007). Football academies and the migration of African football labour to Europe. Journal of Sport and Social Issues 31(2): 143–161.
Blatter, S. (2008). Football Gives Hope. Available from: http://www.fifa.com/aboutfifa/organisation/president/news/newsid=741873/index.html [last accessed January 04, 2013)
Brooking, T. (2007). English football under threat. Available from: http://news.bbc.co.uk/sport1/hi/football/6975955.stm [last accessed January 04, 2013)
Darby, P., G. Akindes, and M. Kirwin. (2007). Football academies and the migration of African football labour to Europe. Journal of Sport and Social Issues 31(2): 143–161.
Del Bosque, V. (2012). Spain Coach Vicente Del Bosque Insists Foreign Premier League Players Are Not Damaging The English National Team. Available from: http://www.goal.com/en-india/news/477/euro-2012/2010/09/22/2131418/spain-coach-vicente-del-bosque-insists-foreign-premier [last accessed January 04, 2013)
Elliott, R. (2012). New Europe, new chances? The migration of professional footballers to Poland’s Ekstraklasa. International Review for the Sociology of Sport 0(0) 1–16
Elliott, R. and J. Harris. (2011). Crossing the Atlantic from football to soccer: Preliminary observations on the migrations of English players and the internationalization of major league soccer. WorkingUSA: The Journal of Labour and Society 14(4): 555–568.
Elliott, R., and G. Weedon. (2010) Foreign players in the premier academy league: ‘Feet-drain’ or ‘feet-exchange’? International Review for the Sociology of Sport 46(1): 61–75.
European Commission (2008) Press Release IP/08/807. Brussels: European Commission.
Ferguson, A. (2007). Ferguson calls for a cap on foreign players. Available from: http://www.guardian.co.uk/football/2007/nov/06/newsstory.arsenal [last accessed January 04, 2013)
Fischer, P. A., M. Reiner, and T. Straubhaar.(1997). Interdependencies between development and migration. In: Hammar T, Brochmann G, Tamas K and Faist T (eds) International Migration, Immobility and Development: Multidisciplinary Perspectives. Oxford: Berg, 91–132.
Iredale, R., and R. Appleyard. (2001) Introduction to the special issue on the international migration of the highly skilled. International Migration 39(5): 3–6
Klein, A. (1989). Baseball as underdevelopment: Dominic resistance, and baseball. Dialectical Anthropology 13: 301–321.
Klein, A. (1991a). Sport and culture as contested terrain: Americanisation in the Caribbean. Sociology of Sport Journal 8(1): 79–85.
Klein A (1991b) Sugarball: The American Game, the Dominican Dream. New Haven, CT: Yale University Press
Klein, A. (2006). Growing the Game: Baseball and Globalization. New Haven, CT: Yale University Press.
Lanfranchi, P., and M. Taylor. (2001). Moving with the Ball: The Migration of Professional Footballers. Oxford: Berg.
Magee, J., and J. Sugden. (2002). The world at their feet? Professional football and international labour migration. Journal of Sport and Social Issues 26(4): 421–437.
Maguire, J. (1999). Global Sport: Identities, Societies, Civilizations. Cambridge: Polity Press
Maguire, J. (2004). Sport Labor Migration Research Revisited. Journal of Sport & Social Issues. 28, 477-482.
Maguire, J. and R. Pearton. (2000). The impact of elite labour migration on the identification, selection and development of European soccer players. Journal of Sports Sciences 18: 759–769.
Maguire, J., and D. Stead. (1998). Border crossings: Soccer labour migration and the European Union. International Review for the Sociology of Sport 33(1): 59–73.
Maguire, J., G. Jarvie, L. Mansfield, and J. Bradley. (2002). Sport Worlds: A Sociological Perspective. Champaign, IL: Human Kinetics.
Maldini, C. (2000). In Maguire, J.A., and M. Falcous: Sport and Migration: Borders, Boundaries and Crossings
Moorhouse, H. F. (1994). Blue bonnets over the border: Scotland and the migration of footballers. In: Bale J and Maguire J (eds) The Global Sports Arena: Athletic Migration in an Interdependent World. London: Frank Cass, 78–96.
Molnar, G., and J. Maguire. (2008). Hungarian footballers on the move: Issues and observations on the first migratory phase. Sport in Society 11(1): 74–89.
Poli, R. (2010). African migrants in Asian and European football: hopes and realities. Sport in Society. 13, 1001-1011.
Poli, R. (2010). Understanding globalization through football: The new international division of labour, migratory channels and transnational trade circuits. International Review for the Sociology of Sport. 45, 491-506.
Poli R., L. Ravenel, and R. Besson. (2011). Annual Review of the European Football Players’ Labour Market. Neuchâtel: Professional Football Players Observatory.
Soldberg, H.A., and K.K. Haugen. (2008). The international trade of players in European club football: consequences for national teams. International Trade of Players. Unknown, 79-93
Stead, D., and J. Maguire. (2000). Rite de passage or passage to riches? The motivation and objectives of Nordic/Scandinavian players in English League soccer. Journal of Sport and Social Issues 24(1): 36–60.
Storey, D. (2011). Football, place and migration: foreign footballers in the FA Premier League. Geography. 96, 86-94.
Storey, D. (2011). Sport and Geography. Teaching Geography. Unknown, 67-69.
Taylor, M. (2006). Global players? Football, migration and globalisation: 1930-2000. Historical Social Research 31(1): 7–30.
Taylor, G. (2007). Meltdown: The Nationality of Premier League Players and the Future of English Football. London: Professional Footballers’ Association.
Vertovec, S. (2007). Super-Diversity in Britain. Available from: from http://www.academon.com/research-paper/super-diversity-in-britain-96649/
[last accessed January 04, 2013]
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‘Why foreign players migrate and the effect their involvement has had on English football since the inception of the Premier League’ (Part 2)
Following on from part one of this blog we’ll take a look at some of the reasons and explanations for this dramatic intensification of foreign player migration to Europe, and particularly to England.
Elite labour migration is now an established component of global sports (Maguire & Pearton, 2000), however national and transcontinental migration of highly skilled workers is not a new phenomenon (Lanfranchi & Taylor, 2001), and has become a prominent feature in global sports (Maguire, 1999; Maguire et al., 2000) such as association football. Migration in football is as old as the game itself (Taylor, 2006), and these migratory patterns have been identified as far back as the late 19th century in which heralded the inception of the Football League. However, these migrations were largely undergone by other British players from Scotland, Northern Ireland and Wales (Moorhouse, 1994). International recruitment of foreign players to England became more prominent during the post-war period, with an influx of migrants from the Commonwealth nations such as Northern Europe, Scandinavia, and the U.S, all of which shared lingual, colonial, or trading relations with England (McGovern, 2002).
Fast forward to the inaugural season of the Premier League in 1992/93 and further research shows us that during the past 20 years we have seen a dramatic intensification in the migration of foreign players to England (Elliott, 2012; Poli et al., 2011), of whom, have been described as one of the most ‘ubiquitous’ factors towards the continuing globalisation of the game within the 21st century (Elliott, 2012). In-fact on the first day of the 1992/93 Premier League season there were only 11 foreign players in the starting line-ups for Premier League clubs. Since then this number has grown exponentially, and by the 2001/02 season foreign players were the new majority. The Images that follow give a great indication of just how diverse our footballing culture has become in England over the past two decades.
There are a number of reasons that have been established for this dramatic intensification of foreign player migration to England, and they are not just limited to economic factors (Elliott & Harris, 2011). 
With the reinstatement of British clubs into European competitions following a ban in the late 1980’s, and the establishment of the prestigious Champions League cup competition (Maguire & Pearton, 2000), complete with its subsequent high levels of economic reward for both clubs and players we begin to see the ‘pull’ factors at work. Furthermore, the Marc Bosman European court case in December of 1995 resulted in the abandonment of quota systems allowing a greater level of freedom of contractual movement for foreign players within EU countries (Taylor, 2006), as it was proven to be in direct violation of Article 39 of the EC Treaty (now Article 45) of the Treaty on the functioning of the European Union law.
Another prominent feature of the migration followed the Taylor Report in 1990 which resulted in British football becoming a much safer environment resulting in foreign players beginning to show increased interests in migrating to England to ply their trade – which was in stark contrast to the 1980’s where British football was on its knees dying a hooligans death – and is arguably due to a dramatic influx of revenue made available through new media and sponsorship deals (Magee & Sugden, 2002) that Premier League clubs now enjoy as a result of their alliance with BskyB (Maguire & Pearton, 2000). Consequently, this had also lead to the dramatically increased and inflated salaries that professional footballers now demand. The previous has become a popular explanation amongst some academics who believe it the principle reason for migration, and describe it as the ‘mercenary’ (Maguire, 1996) desire to secure the lucrative financial rewards offered by clubs (Andreff, 2009). This desire for financial reward is, however, a more appropriate singular suggestion for migration outside of the sporting context, as highly skilled workers often migrate in order to exploit the positive wage disparities available abroad (Fischer et al., 1997).
The ‘mercenary’ desire may undoubtedly influence some players’ decision to migrate; however, it cannot be described as the only antecedent that influences these choices. Research has shown us that the practice of players ‘following the money’ (Maguire & Pearton, 2000) is part of a broader set of processes that incorporate political, historical, cultural, and geographical patterns.
There has also been a wealth of research (Elliott, 2012; Maguire and Stead, 1998; Molnar and Maguire, 2008; Stead and Maguire, 2000) that further examines the motives for the migration of foreign players, including their need to seek professional sporting experiences, coupled with the desire to test one’s ability at the highest levels – something that they cannot always achieve at the currently level offered to them in their native land. On the other hand, some players migrate only to where it is easier to become culturally assimilated, which perhaps explains why the British rarely move abroad. However, the majority of players who migrate aim to gravitate towards the core in football e.g. the Premier League or one of the other ‘top 5’ leagues in Europe.
Conversely, there are also many ‘push’ factors which force migration, including civil wars such as the many that disrupted Yugoslavia between 1991-1999. This initiated the movements abroad of many players from Croatia, Bosnia, Slovenia and Serbia (Maguire & Pearton, 2000) to Germany which is now why we see the Budesliga overflowing with Eastern European talent. Furthermore, the over-production of indigenous talent can often result in a serious lack of playing opportunities for indigenous players, thereby forcing them to leave to find pastures new to earn a living. Finally, in some cases even being expelled from a particular league or even being exiled from the country it-self has forced some players to find a new country to ply their trade (Elliott, 2012).
In summary we can see that there is a wide variety of ‘push’ and ‘pull’ factors that are not just limited to the huge sums of financial reward that have contributed to the mass migration of foreign players to European shores, but in some cases extreme events such as civil war are the catalyst. I believe it is important to understand and highlight the relationship that BskyB broadcasting has had on English football and migration since the Premier Leagues inaugural season. A tremendous amount of wealth has come from the relationship, and still there seems to be no plateau in the broadcasting rights fees. For the next three years BskyB and BT have paid the Premier League an incredible £3.018billion for the domestic TV rights, a remarkable 70% increase over the previous deal of £1.782billion, which is allowing Premier League club the license to dominate the foreign transfer markets, but although frequent are the calls for quotas systems and limitations to foreign player involvement, all in the name of ‘preserving English football’ of course. We must surely ask ourselves would we have the weekly spectacle we have enjoyed for the past two decades without the influx of these talented footballers?
In part 3 of this blog I will further analyse and address the aforementioned perceived negative effects that foreign players have had on the development of indigenous talent in this country, and will attempt to uncover whether these perceptions actually hold any truth.
References
Andreff, W. (2009). The economic effect of ‘Muscle-Drain’ in sport. In: Walters G and Rossi G (eds) Labour Market Migration in European Football: Key Issues and Challenges. London: Birkbeck Sports Business Centre, pp. 9–31.
Anon. (2010). In Elliott and Weedon’s (2010). Foreign players in the premier academy league: ‘Feet-drain’ or ‘feet-exchange’? International Review for the Sociology of Sport 46(1): 61–75.
Blatter, S. (2003). In Darby, P., G. Akindes, and M. Kirwin (2007). Football academies and the migration of African football labour to Europe. Journal of Sport and Social Issues 31(2): 143–161.
Blatter, S. (2008). Football Gives Hope. Available from: http://www.fifa.com/aboutfifa/organisation/president/news/newsid=741873/index.html [last accessed January 04, 2013)
Brooking, T. (2007). English football under threat. Available from: http://news.bbc.co.uk/sport1/hi/football/6975955.stm [last accessed January 04, 2013
Darby, P., G. Akindes, and M. Kirwin. (2007). Football academies and the migration of African football labour to Europe. Journal of Sport and Social Issues 31(2): 143–161.
Del Bosque, V. (2012). Spain Coach Vicente Del Bosque Insists Foreign Premier League Players Are Not Damaging The English National Team. Available from: http://www.goal.com/en-india/news/477/euro-2012/2010/09/22/2131418/spain-coach-vicente-del-bosque-insists-foreign-premier [last accessed January 04, 2013)
Elliott, R. (2012). New Europe, new chances? The migration of professional footballers to Poland’s Ekstraklasa. International Review for the Sociology of Sport 0(0) 1–16
Elliott, R. and J. Harris. (2011). Crossing the Atlantic from football to soccer: Preliminary observations on the migrations of English players and the internationalization of major league soccer. WorkingUSA: The Journal of Labour and Society 14(4): 555–568.
Elliott, R., and G. Weedon. (2010) Foreign players in the premier academy league: ‘Feet-drain’ or ‘feet-exchange’? International Review for the Sociology of Sport 46(1): 61–75.
European Commission (2008) Press Release IP/08/807. Brussels: European Commission.
Ferguson, A. (2007). Ferguson calls for a cap on foreign players. Available from: http://www.guardian.co.uk/football/2007/nov/06/newsstory.arsenal [last accessed January 04, 2013)
Fischer, P. A., M. Reiner, and T. Straubhaar. (1997). Interdependencies between development and migration. In: Hammar T, Brochmann G, Tamas K and Faist T (eds) International Migration, Immobility and Development: Multidisciplinary Perspectives. Oxford: Berg, 91–132.
Iredale, R., and R. Appleyard. (2001) Introduction to the special issue on the international migration of the highly skilled. International Migration 39(5): 3–6.
Klein, A. (1989). Baseball as underdevelopment: Dominic resistance, and baseball. Dialectical Anthropology 13: 301–321.
Klein, A. (1991a). Sport and culture as contested terrain: Americanisation in the Caribbean. Sociology of Sport Journal 8(1): 79–85.
Klein A (1991b) Sugarball: The American Game, the Dominican Dream. New Haven, CT: Yale University Press
Klein, A. (2006). Growing the Game: Baseball and Globalization. New Haven, CT: Yale University Press.
Lanfranchi, P., and M. Taylor. (2001). Moving with the Ball: The Migration of Professional Footballers. Oxford: Berg.
Magee, J., and J. Sugden. (2002). The world at their feet? Professional football and international labour migration. Journal of Sport and Social Issues 26(4): 421–437.
Maguire, J. (1999). Global Sport: Identities, Societies, Civilizations. Cambridge: Polity Press
Maguire, J. (2004). Sport Labor Migration Research Revisited. Journal of Sport & Social Issues. 28, 477-482.
Maguire, J. and R. Pearton. (2000). The impact of elite labour migration on the identification, selection and development of European soccer players. Journal of Sports Sciences 18: 759–769.
Maguire, J., and D. Stead. (1998). Border crossings: Soccer labour migration and the European Union. International Review for the Sociology of Sport 33(1): 59–73.
Maguire, J., G. Jarvie, L. Mansfield, and J. Bradley. (2002). Sport Worlds: A Sociological Perspective. Champaign, IL: Human Kinetics.
Maldini, C. (2000). In Maguire, J.A., and M. Falcous: Sport and Migration: Borders, Boundaries and Crossings
Moorhouse, H. F. (1994). Blue bonnets over the border: Scotland and the migration of footballers. In: Bale J and Maguire J (eds) The Global Sports Arena: Athletic Migration in an Interdependent World. London: Frank Cass, 78–96.
Molnar, G., and J. Maguire. (2008). Hungarian footballers on the move: Issues and observations on the first migratory phase. Sport in Society 11(1): 74–89.
Poli, R. (2010). African migrants in Asian and European football: hopes and realities. Sport in Society. 13, 1001-1011.
Poli, R. (2010). Understanding globalization through football: The new international division of labour, migratory channels and transnational trade circuits. International Review for the Sociology of Sport. 45, 491-506.
Poli R., L. Ravenel, and R. Besson. (2011). Annual Review of the European Football Players’ Labour Market. Neuchâtel: Professional Football Players Observatory.
Soldberg, H.A., and K.K. Haugen. (2008). The international trade of players in European club football: consequences for national teams. International Trade of Players. Unknown, 79-93
Stead, D., and J. Maguire. (2000). Rite de passage or passage to riches? The motivation and objectives of Nordic/Scandinavian players in English League soccer. Journal of Sport and Social Issues 24(1): 36–60.
Storey, D. (2011). Football, place and migration: foreign footballers in the FA Premier League. Geography. 96, 86-94.
Storey, D. (2011). Sport and Geography. Teaching Geography. Unknown, 67-69.
Taylor, M. (2006). Global players? Football, migration and globalisation: 1930-2000. Historical Social Research 31(1): 7–30.
Taylor, G. (2007). Meltdown: The Nationality of Premier League Players and the Future of English Football. London: Professional Footballers’ Association.
Vertovec, S. (2007). Super-Diversity in Britain. Available from: from http://www.academon.com/research-paper/super-diversity-in-britain-96649/ [last accessed January 04, 2013]
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‘Why foreign players migrate and the effect their involvement has had on English football since the inception of the Premier League’ (Part 1)
I’d like to begin my first blog by thanking Leo for inviting me along on this journey. I very much look forward to adding to the fantastic work he has done already. The first issue I would like to discuss is the perceived effect that foreign players are having on the English game. It’s a topic I find very interesting, and I feel is often blown out of proportion by everyone involved in the game today. The blogs that follow will be an investigation and analysis of the current state of the issue and the major views involved.
There has been a common and growing concern for a number of years amongst English football fans (Solberg & Haugen, 2008) and senior figures in world football – FIFA President Sepp Blatter, UEFA President Michel Platini, and English PFA Chief Executive Gordon Taylor – that the mass migration of foreign players to the English Premier League is having a detrimental effect on the English game, and its development of young English talent (Ferguson, 2007; Taylor, 2007). When speaking to BBC’s Inside Sport Sir Trevor Brooking (2007) stated that “you [can’t] underestimate [the threat of foreign players] and people are [only] just starting to identify it”. These concerns lie in accordance with the PFA’s ‘Meltdown’ report, which was commissioned following England’s failure to qualify for Euro 2008. Taylor (2007) states within the report that:
“The price of the unrestricted flow of foreign players into England has been the loss of a generation of English players. Indeed, we are close to losing a second generation and if current trends continue – as all evidence suggests they will – we are, at best, ten years away from having too few English players to mount a serious World Cup campaign.”
These concerns have continued to grow after England’s more recent mediocre performances during the 2010 World Cup and Euro 2012. However, some academics (Elliott & Weedon, 2010) suggest these views and concerns have been sensationalized by the British media and are in-fact not even close to the truth.
Three main arguments that have arisen from the on-going debate on foreign players: firstly, that a process of ‘feet-drain’ is occurring in English football, with foreign players stifling indigenous player development, and replacing them, or taking their opportunities for first team football (Elliott & Weedon, 2010). Secondly, that at the ‘donor’ level a process of ‘deskilling’ is occurring outside of England in the lesser economically developed countries such as Africa (Maguire et al., 2002; Maguire & Pearton, 2000). Thirdly, the migration of foreign players particularly to England is creating an imbalance in world football which is a view firmly held by FIFA President, Sepp Blatter (2008), who declared that:
“It’s not morally right, and competition loses all balance, when the big clubs buy 25 top players to deprive other teams of them and then hoard them because they can only have 11 players on the park.”
Now I have introduced this subject to you, I’d like to hear you initial views and opinions. Feel free to contribute to the discussion via the comments box. In part two of this blog I will discuss a brief history of elite labour migration, and explore some of the reasons for why we have seen this dramatic intensification of foreign player migrating to England and Europe.
References:
Blatter, S. (2008). Football Gives Hope. Available from: http://www.fifa.com/aboutfifa/organisation/president/news/newsid=741873/index.html [last accessed January 04, 2013)
Brooking, T. (2007). English football under threat. Available from: http://news.bbc.co.uk/sport1/hi/football/6975955.stm [last accessed January 04, 2013)
Elliott, R., and G. Weedon. (2010) Foreign players in the premier academy league: ‘Feet-drain’ or ‘feet-exchange’? International Review for the Sociology of Sport 46(1): 61–75.
Ferguson, A. (2007). Ferguson calls for a cap on foreign players. Available from: http://www.guardian.co.uk/football/2007/nov/06/newsstory.arsenal [last accessed January 04, 2013)
Maguire, J. and R. Pearton. (2000). The impact of elite labour migration on the identification, selection and development of European soccer players. Journal of Sports Sciences 18: 759–769.
Maguire, J., G. Jarvie, L. Mansfield, and J. Bradley. (2002). Sport Worlds: A Sociological Perspective. Champaign, IL: Human Kinetics.
Soldberg, H.A., and K.K. Haugen. (2008). The international trade of players in European club football: consequences for national teams. International Trade of Players. Unknown, 79-93
Taylor, G. (2007). Meltdown: The Nationality of Premier League Players and the Future of English Football. London: Professional Footballers’ Association.
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Motion Analysis in Football
Nowadays, many coaches start using notational analysis by pen and paper to help their coaching. For example, they count the number of passes, shots and crosses etc to see how the team performed and which area can be improved. Apart from notational analysis, the coaches can improve their coaching by knowing more about motion analysis in football as well. In my previous article (here), I discussed about what motion analysis is. In short, motion analysis is the process of classifying activities according to intensity of movements (Strudwick and Reilly 2001). The three elements that should be considered are intensity (or quality), duration (or distance) and frequency (Carling et al 2005). The activities were coded according to intensity of movement, e.g. walking, jogging, cruising and sprinting. By using the information, the coaches can design specific drills to fit the football players in different levels and positions in order to achieve higher efficiency of improving performance.
Work rate activity profiles
One of the early researches about motion analysis in football was from Reilly and Thomas (1976). They found that the overall distance covered by outfield player during a match consists of 24% walking, 36% jogging, 20% cruising, 11% sprinting, 7% moving backwards and 2% moving in possession of the ball. The below figure visualises the above finding.
Figure 1 Relative distances covered in different categories of activity for outfield players during soccer match-play
They found two things about the ratio of low-high intensity exercise. The ratio is 2.2 to 1 in terms of distance covered and 7 to 1 in terms of time. Different researchers have different activity profiles. For example, Bradley et al (2009) classified players’ activities into standing, walking, jogging, running, high-speed running and sprinting. Generally, the activities would be classified into two categories: low to moderate intensity activity and high intensity activity and different researches had similar results. Bradley et al (2009) found that low-intensity activity represented 85.4% of total time. Bloomfield et al (2007) had a similar finding that 80-90% of performance is spent in low to moderate intensity activity whereas the remaining 10-20% are high intensity activities. From the above figure, you may realize that only 2% of the total distance covered by top players is with the ball, that means vast majority of actions are “off the ball”, for instance, running into space, support teammates, tracking opposing players. If you are a coach, try to ask yourself “Should I put more effort and time coaching players without the ball rather than just coaching the player with the ball?”. Some other findings such as player has a short rest pause of only 3s every 2 minutes and players generally have to run with effort (cruise or sprint) every 30s (Reilly and Williams 2003) may be useful for the coaches as well.
For the mean distance covered, Strudwick and Reilly (2001) stated that the top division players in the 1970s covered a mean distance of 8680m. In contemporary premier league the figure became 11264m. They suggested that it was because there are more passes, runs with the ball, dribbles and crosses which lead to the increase in the tempo of games. In the research of Bradley et al (2009), the result is 10714m. If you are a coach of adult’s team, the information can be a benchmark for your reference about distance covered for your players.
Does work rate and movement vary by the different positional roles?
Some coaches may realize there should be some differences but they may not realize what the differences are. There are positional differences in work rate and fitness levels. In terms of distance covered, midfield players have the greatest distance covered which is reasonable because they acts as links between defence and attack (Reilly and Thomas 1976)(Ekblom 1986)(Bangsbo et al 1991). This finding was supported by other research. For example, midfielders were engaged in a significantly less amount of time standing still and shuffling and the most time running and sprinting (Bloomfield et al 2007). Greatest distance covered sprinting were found in strikers and midfield players (Reilly and Williams 2003). In terms of the difference between full backs and centre backs, full backs covered more overall distance than the centre backs, but less distance sprinting (Strudwick and Reilly 2001)(Reilly and Williams 2003).
Apart from work rate, motion analysis analyse movement as well. There are different movement characteristics for different positions. Here is the list of findings from different researchers.
Defenders:
- Perform the highest amount of jogging, skipping and shuffling movements and spend a significantly less amount of time sprinting and running than the other positions (Bloomfield et al 2007)
- More body strength in order to compete with the strikers
- Highest amount of backwards and lateral movements (Rienze et al 2000)
- More turns of 0-90 degree(Bloomfield et al 2007)
- Ability to move backwards and sideways is important for defenders (Carling et al 2005)
- To be heavier and with higher BMI, although only slightly taller, than midfielders (Bloomfield et al 2005)
Midfielders
- Were engaged in a significantly less amount of time standing still and shuffling and the most time running and sprinting (Bloomfield et al 2007)
- Perform the most directly forward movements (Rienze et al 2000)
- More diagonal and arc movements (Bloomfield et al 2007)
- More turns of 270-360 degree (Bloomfield et al 2007)
Strikers/Forwards:
- Perform the most of the other types movements (jumping, landing, diving, sliding slowing downing, falling and getting up)
- Perform the most physical contact at high intensity,
- More stopping, these activities produce shearing forces on the lower limbs and Besier et al (2001) suggested that strength training and prehabilitation practices must be adopted and emphasised.
- More diagonal and arc movements (Bloomfield et al 2007)
- More turns of 270-360 degree (Bloomfield et al 2007)
- Forwards tend to receive the ball when sprinting (Carling et al 2005)
- To be heavier and with higher BMI, although only slightly taller, than midfielders (Bloomfield et al 2005)
I hope these are useful for the coaches to know more about different requirements in different positions in terms of work rate, movement and even body strength.
Does work rate vary by the styles of play?
Although all the work rate research done by different researchers are facts, we should think about whether it is ‘all of the facts’. Are they always 100% right and can be applied to all situations? I think style of play is a factor which can affect the work rate of a team. Some researchers had the same view also (Bradley et al 2009)(Reilly and Williams 2003). In possession play, the pace of the game is slowed down, the attacking moves are delayed and the players will wait until opportunities rises. In direct play, the team tries to raise the pace of the game by passing the ball quickly in order to transfer the ball quickly from defence to attack to create opportunities. Therefore, the team would prefer long passes rather than a sequence of short passes. Apart from possession play and direct play which are the most discussed styles of play, we shouldn’t ignore Total football and South American style. I don’t know much about these two styles but I think the work rate requirement of Total football would be similar to direct play as they exchanges positions frequently. South American style is more rhythmic and the overall distance covered is 1.5km less than in the English Premier League (Rienze et al 2000).
Summary
In the 90-minute match time, 80-90% of performance is spent in low to moderate intensity activity whereas the remaining 10-20% are high intensity activities. However, we must remember that most of the key incidents of the game are happened within those 10-20% high intensity activities. There are significant differences existing between strikers, midfield players and defenders in terms of work rate, activity profiles and movements. For example, defenders have the most of backwards and lateral movements. Midfielders covered the greatest distance. Strikers/ forwards tend to receive the ball when sprinting. I hope this article would be useful for the coaches to know more about different requirements of different positions in order to design more specific conditioning programs for the players. Defenders and strikers need speed and agility type drills while midfielders need interval running over longer distances.
References
BANGSBO, J., L. NORREGAARD and F. THORSO, 1991. Activity profile of professional soccer. Canadian Journal of Sports Science, 16, 110-16
BESIER, T.F., D.G. LLOYD, J.L. COCHRANE and T.R. ACKLAND, 2001. External loading of the knee joint during running and cutting manoeuvres. Medicine and Science in Sport and Exercise, 33, 1168-1175
BLOOMFIELD, J., R.C.J. POLMAN, R. BUTTERLY and P.G. O’DONOGHUE, 2005. An analysis of quality and body composition of four European soccer leagues. Journal of Sports Medicine and Physical Fitness, 45, 58-67
BLOOMFIELD, J., R. POLMAN and P. O’DONOGHUE, 2007. Physical demands of different positions in FA Premier League Soccer. Journal of Sports Science and Medicine, 6, 63-70
BRADLEY, P.S., W. SHELDON, B. WOOSTER, P.OLSEN, P.BOANAS and P. KRUSTRUP, 2009. High-intensity running in English FA Premier League soccer matches. Journal of Sports Sciences, 27(2), 159-168
CARLING, C. et al., 2005. Handbook of Soccer Match Analysis. Oxon: Routledge
EKBLOM, B., 1986. Applied physiology of soccer. Sports Medicine, 3, 50-60
REILLY, T. and A., M. WILLIAMS, 2003. Science and Soccer. 2nd ed. Oxon: Routledge
REILLY, T. and V. THOMAS, 1976. A motion analysis of work-rate in different positional roles in professional football match-play. Journal of Human Movement Studies, 2, 87-97
RIENZE, E., B. DRUST, T. REILLY, J.E.L. CARTER and A. MARTIN, 2000. Investigation of anthropometric and work-rate profiles of elite South American international players. Journal of Sports Medicine and Physical Fitness, 40, 162-9
STRUDWICK, T. and T. REILLY, 2001. Work-rate Profiles of Elite Premier League Football Players. Journal of Exercise Science, 4(2)
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What are Performance Analysis and Match Analysis?
Fifteen years ago, there may be only a few big Premier League football clubs had a performance analysis department. Nowadays, even a League 2 club like Aldershot for which I am working have set up a Performance Analysis department this season. It is a fast growing industry and I firmly believe it will keep growing for the next ten years at least.
Where does it come from?
If we want to know where it came from, sports science has to be mentioned. The first academic programmes in sports science were studied in the UK in 1975. Initially, it included biology, biochemistry, physiology, biomechanics, mathematics, psychology and sociology. Nowadays, the sports science programmes may include economics, recreation sport development, coaching and computer science also (Reilly and Williams 2003). The first Bachelor of Science degree which combined science and football together was offered at Liverpool John Moores University in 1997. Performance analysis in football was one of the core modules.
Difference between Performance Analysis and Match Analysis
You may realize both terms are used in books and articles as they are very similar. In my opinion, match analysis focuses everything about the matches, e.g. post-match analysis, opposition analysis (tactics and strategies). Performance analysis has a wider coverage and includes more disciplines. In short, match analysis is part of the performance analysis. Apart from match analysis, performance analysis includes player recruitment, player evaluation, training analysis, trend analysis and even referees analysis (Prozone 2009). However, you may realize that some of these disciplines are just the further development of match analysis, e.g. player evaluation and trend analysis. Therefore, I think match analysis is the core part of performance analysis. I will focuses on match analysis in the following paragraphs.
Why match analysis is undertaken?
Some people may argue that soccer is an art, especially if you watch the Zinadine Zidane played. I won’t deny that as I agree playing and coaching soccer are arts but I think science can be a part of soccer as well. In terms of preparation, science information is helpful for coaches and trainers to make decisions and judgement. For one’s own team, the information can be used to identify strengths and weaknesses. For opposition, we can use data to counter opposing strengths and exploit weaknesses. Moreover, match analysis can be used to evaluate whether the training programmes improve the match performance or not (Carling et al. 2005). The information is a big set of data and coach can’t remember all of it during the game. Franks and Miller (1986) found that international level soccer coaches could only recollect 30% of the key elements that determined successful soccer performance observed. Another research indicated that coaches are able to recall fewer than half of the key incidents (Carling et al. 2005). Another reason is that the coach may not be able to get the information objectively. Neisser (1982) found that the accuracy of memories of events I greatly influenced by many factors, e.g. the beliefs of the observer. In other words, coaches are active observers rather than passive perceivers of information. Their perception of events would not be a copying process but rather a selective and constructive one (Reilly 1996). Then coaches can’t provide an objective and unbiased information. Therefore, match analysis/ performance analysis is needed to provide such information and analysis.
What does match analysis include?
In my opinion, match analysis can be divided into two categories: Notational analysis and Motion analysis.
Notational analysis is a means of recording events so that there is an accurate and objective record of what actually took place (Carling et al. 2005). There should be at least five elements which should be recorded: the position (where?), the players involved (who?), the action concerned (what?), the time (when?) and the outcome of the activity (e.g. successful or unsuccessful, or on target or off target. Generally there are two ways to do it: by hand/manual or by computer. Reep and Benjamin (1968) were the early researchers in hand notation system. They collected data from 3213 matches between 1953 and 1968 and recorded actions such as passing and shooting. Their conclusions were that 80% of goals were resulted from a sequence of three passes or less and 50% of all goals came from possession gained in the final attacking quarter of the pitch. In terms of computerized notation system, Matchviewer of Prozone is a good example which provides the data of passing, heading, shooting, tackling etc. Both systems have their strengths and weaknesses. The following table summarizes part of it.
| Hand/ Manual notational system | Computerized notational system | |
| Strength |
|
|
| Weakness |
|
|
Table 1: Summary of the strengths and weaknesses of hand and computerized notation system
Another category of match analysis is motion analysis which focuses on raw features of an individual’s activity and movement (Carling et al. 2005). It can specify work rates of the players in different positions and distances covered in a game (Reilly and Williams 2003). This analysis is useful in identifying fatigue and differentiating between positional differences in work rate and fitness levels (e.g. ability to move backwards and sideways is important for defenders) (Carling et al. 2005). There are three elements which should be measured: intensity (walking, jogging, cruising and sprinting), duration (or distance) and frequency. Prozone3 is software of Prozone which provides this sort of data. Nowadays, most of the motion analysis would be done by computer as it is difficult for people to record how many metres a player ran in a match. However, in the old days, researchers had to do it by hand. Reilly and Thomas (1976) recorded and analyzed the intensity and extent of discrete activities. They combined hand notation with tape to analyse the movement of the players. They found that a player is in possession of the ball for less than 2% of the game.
Conclusion
Performance analysis is becoming more popular in lower leagues and more football clubs will set up the performance analysis department in future. There is still much room for the development of performance analysis. Match analysis is different from performance analysis but it is the core part of performance analysis. The aim of doing analysis is to provide objective information and analysis for the coach about past performance (either team or individual). The analysis can be done by hand/manual and computer as well. Both systems have their own strengths and weaknesses.
References
CARLING, C. et al., 2005. Handbook of Soccer Match Analysis. Oxon: Routledge
FRANKS, I.M. and MILLER, G., 1986. Eyewitness testimony in sport. Journal of Sport Behavior, 9, 38-45
NEISSER, U., 1982. Memory Observed. San Francisco: CA
PROZONE, 2009. Services [online][viewed 5 September 2012]. Available from: http://www.prozonesports.com/services.html
REEP, C., & BENJAMIN, B., 1968. Skill and chance in association football. Journal of the Royal Statistical Society A, 131, 581-585
REILLY, T., 1996. Science and Soccer. E & FN Spon
REILLY, T. and THOMAS, V., 1976. A motion analysis of work-rate in different positional roles in professional football match-play. Journal of Human Movement Studies, 2, 87-97
REILLY, T. and A., M. WILLIAMS, 2003. Science and Soccer. 2nd ed. Oxon: Routledge
Football Performance Analysis 
