Substitution (association football)

In association football, a substitute is a player who is brought on to the pitch during a match in exchange for an existing player. Substitutions are generally made to replace a player who has become tired or injured, or who is performing poorly, or for tactical reasons (such as bringing a striker on in place of a defender). Unlike some sports (such as American football or ice hockey), a player who has been substituted during a match may take no further part in it.

Most competitions only allow each team to make a maximum of three substitutions during a game, although more substitutions are often permitted in non-competitive fixtures such as friendlies. A fourth substitution in extra time is currently being trialled at several tournaments over a two-year period. Each team nominates a number of players (typically between five and seven, depending on the competition) who may be used as substitutes; these players typically sit in the technical area with the coaches, and are said to be "on the bench".

A player who is noted for frequently making appearances, or scoring important goals, as a substitute is often informally known as a "super sub".

The origin of football substitutes goes back to at least the early 1860s as part of English public school football games. The original use of the term "substitute" in football was to describe the replacement of players who failed to turn up for matches. For example, in 1863, a match reports states: "The Charterhouse eleven played a match in cloisters against some old Carthusians but in consequence of the non-appearance of some of those who were expected it was necessary to provide three substitutes. The substitution of absent players happened as early as the 1850s, for example from Eton College where the term "emergencies" is used. Numerous references to players acting as a "substitute" occur in matches in the mid-1860s where it is not indicated whether these were replacements of absent players or of players injured during the match.

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