Possession (sports)

American footballofficial indicating which team has possession after a fumble

In sports,possessionis physical control of the ball or other implement of play by oneteam,which typically gives that team the opportunity toscore.Sports have different rules governing how possession is kept or lost ( "turned over" ), which affect the strategy of gameplay. The number of possessions or total time of possession are often usefulstatisticsof team or individual performance.

Ingoal-based sports, includingbasketball,all forms offootball,hockey,andlacrosse,the team with possession has the opportunity to score, and is said to be onoffense,while the other team is ondefense.Inbat-and-ball gamesincludingbaseballandcricket,the ball is controlled by the fielding team, which is on defense.

Start of gameplay

Possession at the start of a game (and, in some sports, in a neutral restart) may be determined by several methods, including acoin flip(American football andcricket),home teamstatus (baseball), or by giving the teams an equal opportunity to physically take possession, in what is variously called adropped-ball(association football), aball-up(Australian rules football), ajump ball(basketball), or aface-off(hockey).

Change of possession

Scoring or losing physical control

In several sports, possession is exchanged after the offensive team scores, or when the defensive team physically takes control of a "live" (in play) ball through afumble,interception,steal,or penalty such as afree kickto the defensive side.

Allotted number of plays

Ingridiron football,possession is additionally controlled through a series of allotted plays calleddowns,during which the offensive team must move the ball a certain distance down the field, or lose possession. Similarly, inrugby league,offensive teams havesix chancesto score, or tackles, before losing possession. Inlimited overs cricket,the offense has a limited number of legaldeliveries,which are periods of play, in each of which a defensive player throws the ball (according to certain rules) for an offensive player to hit and attempt to help his team score off of, before the offense'sscoring turnends and the defense must surrender possession of the ball.

Shot clocks

In some timed sports, including basketball and lacrosse, a team with possession and a lead in score may try to "run time off the clock" by keeping the ball but not attempting to score, in order to deny the opposing team possession. Ashot clockspeeds gameplay by requiring teams to attempt to score within a certain period of time or lose possession.

Bat-and-ball sports

In bat-and-ball sports, the teams switch offensive and defensive roles after theendof one of the batting (offensive) team's scoring turns (called an "inning"or"innings"), which is brought about by the defense getting a certain number of offensive players"out"by various rules in each game.

Turnovers by sport

Turnovers in different sports include:

• Turnover (basketball),resulting from a steal, or a player going out of bounds, committing a violation (including exceeding the shot clock), or committing an offensive foul
• Turnover (gridiron football),in American and Canadian football, when the offense loses possession of the football because of a fumble, interception, or on downs
• Turnover (rugby league),when a team loses possession or at the end of a team's six tackles
• Turnover (rugby union),when a team loses possession in a ruck or a maul

Calculation and statistical use

Inassociation football,several methods have been used to measure teams' possession percentage, including both clock time and proportion of passes by a team.It has historically been assumed that a greater possession percentage correlates with a scoring advantage, however, at least one study has questioned this assumption.