Water polo

Water polo is a team water sport. It is the oldest continuous Olympic team sport. The playing team consists of six field players and one goalkeeper with a maximum of six substitutes. The winner of the game is the team that scores more goals. Gameplay involves swimming, players passing the ball while being defended by opponents, and scoring by throwing into a net defended by a goalie.
Water polo, therefore, has strong similarities to the land-based game of team handball. The frequency of 'man-up' (or 'power play') situations also draws comparisons with ice hockey.

Seven players from each team (six field players and a goalkeeper) are allowed in the playing area of the pool during game play. Visiting team field players wear numbered and usually white caps, and home team field players wear usually dark blue caps (though any other contrasting colors are now allowed); both goalies wear quartered red caps, numbered "1".

Both teams may substitute players. During game play, players enter and exit in the corner of the pool, or in front of their bench; when play is stopped, they may enter or exit anywhere.