Born from classic polo, water polo was initially contested with players riding floating barrels meant to resemble horses. The modern version is based on a set of rules that were introduced in Scotland in 1880. Each team was allowed seven players in the pool at once and the dimensions of the goal were fixed. Men’s water polo has been an Olympic sport since 1900 and the women’s sport was introduced 100 years later in Sydney. It has been on the Pan American Games program since 1951.
Every match is comprised of four quarters that run eight minutes in length. The object of the game is to try to score on the opposing team. None of the players is permitted to touch the bottom of the pool throughout the game. It is also prohibited for players to hold on to the ball with both hands or, except in the case of the goaltender, to strike the ball with their fist.
The playing field must be at least 1.8m deep x 30m long x 20m wide with a 3m x .9m goal at each end. Ropes define the playing field. Flags along the side of the pool mark the centre line, the goal line and lines that are 2 metres and 5 metres from the goal line.
Each team lines up along its goal lines to begin the play. When the referee blows the whistle, the players sprint to half pool where the ball is released. Once a team gains possession of the ball, its players must shoot the ball toward the net within 30 seconds. Players can advance the ball by passing, shooting or moving the ball while swimming. Offensive players can cross the 2-metre line only if the ball is with them or precedes them.