References used introduction

RULES OF WATER POLO
The water polo match consists of four quarters respectively, 8 minutes each. The countdown in the quarter begins with the first touch of the ball. Each team has only 25 seconds to attack and after 25 seconds the ball passes to the opposing team. The rules allow each team to take 4 time-outs per game at a regular time and 1 time-out per game at extra time. Only the team that owns the ball can ask for the time-out.

There can be 6 field players and 1 goalkeeper on the field at the same time. The rules of water polo do not allow: to attack a player who isn’t owning a ball; to heat, drag and hold a player who isn’t owning a ball; to heat a ball. Having made a gross blunder, the player leaves from water for 15 seconds or until the end of the opponent's attack time. At the end of the penalty time, the player must return to the game. A non-gross blunder is punished by a free throw, which can be sent directly to the gates of the opponent. The player who has earned 3 penalties leaves till the end of the game with the right of replacement and sits on the sub bench with the pool hat untied.
FIELD OF PLAY
The size of the playing field for men is 30 x 20 meters, for women 25 x 17 meters. The depth must be at least 1.8 meters. The field needs the following marking: midfield line (white); gate lines (white); 2-, 4-, 7-meter lines (red, yellow, green); the boundary of the playing field. The marking should be clearly visible throughout the game. The marking can be permanent or removable. At the end of the playing field, two meters from the corner of the playing field (opposite the official scoreboard), a red or other bright color sign must be affixed.
Positions
There are seven players in the water from each team at one time. There are six players that play out and one goalkeeper. Unlike most common team sports, there is little positional play; field players will often fill several positions throughout the game as situations demand. These positions usually consist of a center forward, a center back, the two wing players and the two drivers. Players who are skilled in all positions of offense or defense are called utility players. Utility players tend to come off of the bench, though this is not absolute. Certain body types are more suited for particular positions, and left-handed players are especially coveted on the right-hand side of the field, allowing teams to launch two-sided attacks.
Offense
The offensive positions include: one center forward (also called a "set", "hole-set", "center", "setter", "hole", or "2-meter man", located on or near the 2-meter, roughly in the center of the goal), two wings (located on or near the 2-meter, just outside of the goal posts, respectively), two drivers (also called "flats", located on or near the 5-meter, roughly at the goal posts, respectively), and one "point" (usually just behind the 5 meter, roughly in the center of the goal, respectively), positioned farthest from the goal. The wings, drivers and point are often called the perimeter players; while the hole-set directs play. There is a typical numbering system for these positions in U.S. NCAA men's division one polo. Beginning with the offensive wing to the opposing goalie's right side is called one. The flat in a counter clockwise from one is called two. Moving along in the same direction the point player is three, the next flat is four, the final wing is five, and the hole set is called six. Additionally, the position in which a player is can give advantages based on a player's handedness, to improve a shooting or passing angle (for example, the right wing is often left handed).
The center sets up in front of the opposing team's goalie and scores the most individually (especially during lower level play where flats do not have the required strength to effectively shoot from outside or to penetrate and then pass to teammates like the point guard in basketball, or center midfield player in soccer). The center's position nearest to the goal allows explosive shots from close-range.
Defense
Defensive positions are often the same, but just switched from offence to defence. For example, the centre forward or hole set, who directs the attack on offence, on defence is known as "hole D" (also known as set guard, hole guard, hole check, pit defence or two-metre defence), and guards the opposing team's centre forward (also called the hole). Defence can be played man-to-man or in zones, such as a 2–4 (four defenders along the goal line). It can also be played as a combination of the two in what is known as an "M drop" defence, in which the point defender moves away ("sloughs off") his man into a zone in order to better defend the centre position. In this defence, the two wing defenders split the area furthest from the goal, allowing them a clearer lane for the counter-attack if their team recovers the ball.

Gates are set on both sides of the playing field. The gate consists of two uprights and a rectangular crossbar of 0.075 m thickness, facing the playing field and painted white. It must be set strictly in the middle of the gate line and at a distance of at least 0.30 m from the borders of the playing field. The distance between the gate uprights should be 3 m, and the lower edge of the crossbar should be at a height of 0.90 m above the water surface. The minimum water temperature is 16 degrees.