Onside kick

In gridiron football, an onside kick is a kickoff deliberately kicked short. In most kickoffs, the kicking team concedes possession of the ball and tries to kick it as far as possible from its own goal. In an onside kick, the kicking team kicks short in hopes of regaining possession of the ball before the receiving team can control it.

The onside kick is a low-percentage play, generally only seen late in a game when the kicking team is trailing in the score and must retain possession of the ball in order to score before time expires. However, its chances of success increase in a situation where the returning team does not expect it.

Gridiron football originates in rugby football, and so does the onside kick. In rugby, while the forward pass is prohibited, a team in possession may legally kick the ball downfield and recapture possession, provided that the receiver of the kick was onside when the kick was made (i.e., abreast with or behind the kicker.)

This form of onside kick is still legal in Canadian football, just as in rugby. A player of the kicking team (at any kick, not just a free kick) who is "onside" may recover the ball and retain possession for his team. This includes the kicker himself and anyone else behind the ball at the time it was kicked, other than the holder for a place kick.

The form of onside kick available at a free kick in American football (see below) is also available in Canadian football for a kickoff as well, although it is referred to as a short-kick, as all players are onside for a kickoff; however, the kick may well be chipped high instead of bounced, because the players of the receiving team have no particular first right to the ball as in American football (due to the fair catch rule); both sides may play the ball equally, even in the air.

Starting in 1923, the following additional constraints in most forms of American football are relevant to the onside kick:

Unlike during a punt — where if the kicking team catches or recovers the ball, it is "downed" and the receiving team possesses the ball — during a free kick, a ball that has crossed the receiving team's restraining line is normally a live ball, such that if the kicking team catches or recovers the ball it retains possession. "Onside" is therefore now a misnomer in American football; an onside kick is simply any free kick that is kicked in a particular way to give the kicking team the best chance of regaining possession — typically in a diagonal direction and as close to the advancing players from the kicking team as possible.

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