Team tactics as well as individual skills are integral for playing association football. In theory, association football is a very simple game, as illustrated by Kevin Keegan's namely assertion that his tactics for winning a match were to "score more goals than the opposition". Tactical prowess within the sport is nonetheless a craftsmanship of its own, and one of the reasons why managers are paid well on the elite level. Well-organised and ready teams are often seen beating teams with more skillful players on paper. Manuals and books generally cover not only individual skills but tactics as well.[2][3]
Association football teams consist of ten outfield players and one goalkeeper, which makes passing an integral part of game strategy, and is taught to players from a young age. Other skills taught to players on an individual level are dribbling, heading the ball and ball control for receiving the ball. Other skills that are taught individually are jockeying for defenders, and shot stopping for goalkeepers. In terms of complexity, lower levels of the game such as youth leagues, amateur leagues and semi-professional leagues primarily focus on the fundamentals of the game, whereas higher levels of the game – as it regards to professional football teams – will increase complexity and level of detail in strategy of the game.[4][5]
In FIFA 11-a-side competitive fixtures, teams are allowed to substitute up to five players during games. The rules of the competition state that all players and substitutes shall be named before kick-off and anyone not named in the starting lineup who takes to the field of play is considered a substitution.[9] In non-competitive matches, the use of substitutes must be determined before the match begins, except in friendly international matches, where no more than six substitutes may be brought on.[4][10]
The most tired players are generally substituted, but only if their substitutes are well trained to fill in the same role, or if the formation is transformed at the same time to accommodate for the substitution.
Coaches often refrain from substituting defensive players in order not to disrupt the defensive posture of the team. Instead, they often replace ineffective attackers or unimaginative midfielders in order to freshen up the attacking posture and increase their chances of scoring.
For a team that is losing a game, a fresh striker can bring more benefit in circumventing an opposed defence line composed of relatively tired players. For a team that is winning a game, a fresh midfielder or a defender can bring more benefit in strengthening the defence against the opposition's attackers (who may be fresh substitutes themselves). In this situation, for the winning team, it is usually imaginative attacking flair players who are replaced by tough-tackling defensive midfielders or defenders.