12th man (football)

The 12th man or 12th player is a term for fans of teams in eleven-a-side sports games, particularly American football or association football. As most football leagues allow a maximum of eleven players per team on the playing field at a time, referring to a team's fans as the 12th man implies that they have a potentially helpful role in the game. Infrequently, the term has referred to individuals having a notable connection to their football team. In Canadian football, 12 players are usually on the field at one time and the term 13th man is often used to refer to fans. Similarly, in Australian rules football, 18 players are on the field and the fans are often referred to as the 19th man. The term has a different meaning in cricket, referring instead to the first substitute player who fields when a member of the fielding side is injured (the term 6th man has a similar connotation in basketball).

The presence of fans can have a profound impact on how the teams perform, an element in the home advantage. Namely, the home team fans would like to see their team win the game. Thus these fans will often create loud sounds or chant in hopes of distracting, demoralizing and confusing the opposing team while they have possession of the ball; or to persuade a referee to make a favorable decision. Noises are made by shouting, whistling, stomping and various other techniques. Sometimes, the sideline is also referred to as the "12th man" or "12th defender". Since a player is considered down when he steps out of bounds, the sideline effectively acts as an extra defender. This usage is less common than the one referring to the fans.

The first recorded use of the term "twelfth man" was a magazine published by the University of Minnesota in September, 1900, that referred to "the mysterious influence of the twelfth man on the team, the rooter." Later, in the November 1912 edition of The Iowa Alumnus, an alumni publication of the University of Iowa (then known as State University of Iowa), E.A. McGowan described the 1903 game between Iowa and the University of Illinois. In his article, titled "The Twelfth Player" McGowan wrote: "The eleven men had done their best; but the twelfth man on the team (the loyal spirited Iowa rooter) had won the game for old S.U.I."

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