Interchange (Australian rules football)

Interchange (or, colloquially, the bench or interchange bench) is a team position in Australian rules football, consisting of players who are part of the selected team but are not currently on the field of play.

As of the 2016 season, at AFL level, each team is permitted four interchange players, and a maximum of ninety total player interchanges during a game. Players have no limit to the number of times they may individually be changed, and an interchange can occur at any time during the game, including during gameplay.

The four players named on the interchange bench in the teamsheet, which is submitted ninety minutes before the commencement of the game, must be the four interchange players who start on the bench, however they may be substituted immediately if the coach wishes.

Interchange rules are not uniform across all leagues. In the major state leagues, as of 2016, following interchange numbers are permitted:

Representative teams (such as State of Origin teams), practice and exhibition matches often feature an extended interchange bench of up to six or eight players.

At different times during the history of the sport, there have been substitute players (also known as reserves) serving a function distinct from interchange players. A player who begins the game as a substitute may take no part in the game until he is substituted for another player, the latter of whom permanently leaves the field.

The substitute rule was resisted for many years, with the prevailing view in the 1910s and 1920s being that a team should be permitted only to substitute a player in the event of an injury, but that there was no way to rule against a team making a tactical substitution. A single substitute was finally introduced by the Australian National Football Council for the 1930 season, with no restrictions on whether the substitution be used for injury or tactical reasons. A second substitute was introduced in 1946, before the substitutes were replaced by interchange in the 1970s. Additionally, in the AFL between 2011 and 2015, a hybrid interchange–substitution arrangement existed in which there were three interchange players and one substitute; under those rules, the substitute was required to wear a green vest until activated, and the player substituted out of the game donned a red vest. As of 2016, substitution is no longer used in the sport.

In front of the interchange benches is the interchange area (sometimes called the interchange gate), which is a 15-metre stretch of the boundary line, roughly centred between the two teams' benches, through which all players must enter and exit the ground when being interchanged. It is marked on the boundary line with two short lines, perpendicular to the boundary, and sometimes with a slanted end. A player who interchanges outside of this area is not permitted to return for the rest of the game.

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