What Is a Polo Chucker?

Clock Stoppers

• Certain events on the polo playing field automatically stop the match clock for a time out, said SportPolo.com. For instance, the clock stops when a goal is scored. There also is a time out if a horse or rider falls or is injured, or if a horse's bridle or saddle breaks, or if a rider loses his helmet or commits a foul, or when the ball goes out of bounds at the sidelines of the field. The time-out length depends on the situation.

Clock Keeps Running

• The match clock keeps running when a player leaves the field in the middle of a chucker simply to change to a fresh horse, or leaves to replace a broken or lost mallet. If the ball crosses the back line of the field without passing through the goal, the clock keeps running while a defending player hits the ball back into play from the back line.

Resuming Play

• To start a new chucker or resume play after a time out, the opposing teams line up in numerical position order each directly behind the other. An umpire rolls the ball between the two teams in what's known as a throw-in, and play begins again. A typical polo match lasts for around 90 minutes.

Polo Teams

• A horse polo team consists of four players, each of whom is assigned a position number worn on their jerseys. According to SportPolo.com, the Number 1 player is the primary offensive attacker, similar to a forward in hockey or soccer. Number 2 is the primary support player for both offense and defense. Number 3 is the primary defender who seeks to get the ball away from the opposing offense and turn the ball back up the field to the Number 1 or Number 2 player. Number 4 is the goal defender who seeks to deny the opponent any shot on goal and get the ball moving back toward the opponent's goal. Players can use their mallets to interfere with an opponent's swing at the ball. They also can bump each other, similar to a body check in hockey.

Object of Game

• The objective in polo is to use a long-handled bamboo and wood mallet while on horseback to hit a 3.25-inch-diameter wood or plastic ball through the opposing team's goal. Each score is one point. After each score, the teams change sides of the field. Matches are played outdoors on a grass field 300 yards long and 160 yards wide, or about 10 acres, which SportPolo.com says is the largest playing field in organized sports. The field is divided in half at midfield. There's also an indoor polo variant called arena polo, played on a field 300 feet by 150 feet, with only three players per team.

Line of the Ball

• Polo has no set of plays, said SportPolo.com. Instead, match action is based on a concept called "line of the ball." The line of the ball is the direction the ball is traveling after being hit with a mallet. The line of the ball changes each time the ball changes direction. The player who hit the ball has the right of way along the line of the ball and no other player can cross the line of the ball in front of him. But other players can ride parallel to the line of the ball and use their mallets to try and change the ball's direction or block any further swings at the ball. The line of the ball rule is intended to reduce the chance of injury to riders and horses.

Penalty Shots

• The most common foul in polo is when a player illegally crosses the line of the ball. There also are fouls for illegal contact, creating a safety hazard, or for acts of unsportsmanlike conduct. According to SportPolo.com, fouls are called by one of the two umpires refereeing the match and are punished with penalty shots, similar to a free throw in basketball. The goal can be defended or left open, depending on severity of the foul. The umpire also determines the hitting distance for the penalty shot. The more severe the foul, the shorter the hitting distance will be.