Polo is a team game like no other. Although the basic pattern is much like ice hockey, soccer, lacrosse or basketball, it takes two heads, six legs and a pair of arms to play polo.
The fact that the player holds a mallet in one hand and accurately manipulates a 4 1/4 inch ball seven feet away from his shoulder with a hitting surface the size of a pineapple renders the game difficult, but not necessarily unique.
Polo is such a fast and fluid game with so few set plays that it makes team play an unparalleled accomplishment when compared with other sports. The most important ingredient for a player is anticipation, just as in ice hockey, anticipation makes the big difference.
What makes polo so truly unique is, of course, the horse. It isn't just equestrian skill, it's the horse as a being, as an independent ego and ultimately, in the purest form as an alternate ego. The horse is as great a challenge as the game itself, in fact, the two cannot be separated.
Eight players on eight horses combining stunt riding with a juggling act. The objective though, is not a mere show of skill, it's winning the game. It is that competitive desire that drives these players and brings out that sharpened ability; that ability which tests their balance to the extreme and heightens their reflexes and courage to where danger is repeatedly challenged, yet defied over and over again.
Two major concepts are the keys to making sense of a polo game and enjoying it too. One is the underlying philosophy, and the other is a technical feature of the game. The principle is that polo-- good polo, is a team sport! The technical concept is the "line of the ball."
The principle governing the rules of the game is safety. The impact of two 1,000 pound horses colliding at full gallop is something to be avoided at all costs. Even the most responsive horse cannot abruptly halt from a fast gallop to avoid a collision, let alone when a rider is not aware of another horse coming.
If players were permitted to approach the ball from any and all directions, there would be none left to play the game. Imagine an unmarked four-way intersection with cars just speeding though and you can see what we mean.
The line of the ball becomes the sacred principle behind the rules. It is the imaginary line that the ball creates as it travels. The line remains set until the ball changes direction and a new line is formed. A line may only be violated or crossed when there is no safety consideration involved. The umpires, guided by the Rule Book, are the sole judges of all such situations.
The "line of the ball" is the path the player travels to either reach a ball or meet it. When two players ride to the ball, both hoping to hit it, one forward and the other backward, they must ride either side of the line so that both will have access to the ball. When two players ride to the ball from opposing directions, they can only hit the ball on their right (off) side, and that way they remain on different sides of the line to hit the ball.
At times the ball might change directions so quickly that a player might become confused as the the exact line. Or, a player, because of poor horse control, or improper judgment, might cross the line; or a player might err by thinking he has time to cross the line without endangering an oncoming player. In all of these cases, the umpire will blow his whistle for a foul. Depending on the severity of the infraction and the danger factor, a free hit is awarded to the fouled team from as close as 15 yards toward an undefended goal to as far away as 25 yards.
An outdoor polo game consists of six chukkers which each last eight minutes. A different horse is used for each chukker, thus the term "my string of ponies".

Playing Field: The playing field can be set up with or without sideboards. A boarded field measures 160 yards wide by 300 yards long and an unboarded field measures 200 yards wide by 300 yards long. The goals are placed on the end lines midway between the side lines. The posts are placed twenty-four feet apart, are ten feet high, and are made of materials light enough so that they will break in case of a collision.

Equipment: The ball is made of light wood, usually willow, with no covering but white paint or hard plastic. It is 3 1/4 inches in diameter and weighs 5 1/2 ounces. The mallets have cane shafts and heads of ash, set at an angle. The length varies from 49 to 54 inches. Several mounts are required for each player in a game, each horse usually being played only one period

Teams: Four players constitute a team. The Number 1 and Number 2 players are primarily offensive players and advance the ball to the goal. Number 3 is a roving player, and usually the best player on the team. It is his responsibility to be prepared to pass the ball forward, attack the goal himself, or drop back to aid in the defense. The Number 4 or "Back" as he is referred to, is basically responsible for defense, although he may turn a play into an attacking situation much the same as Number 3.

Polo Pony: The Polo Pony is an object of admiration. He is selected for his ability to carry weight at great speed, and for his endurance. Many Thoroughbreds or three-fourth Thoroughbreds are used. A pony's training must make him agile and responsive to every command and impulse of the rider. He becomes so familiar with the various shots and maneuvers that he can often anticipate his rider's wishes. Action of horse and rider alike must be instantaneous to be effective. Thus the pony becomes a player in the game.

Officials: Two mounted umpires officiate on the field and follow the players. If a foul is committed a whistle is blown by either umpire. This stops the game. Both umpires must agree on the penalty to be assessed. Should they disagree, the referee, or third man, located on the sidelines decides. A flagman, stationed behind each goal, assists the umpires by indicating if the ball passed between the goal posts or outside them.

Chukker: Also called a period. There are six chukkers in a polo game, each lasting 7 minutes. If the score is tied at the end of the sixth chukker, a seventh period of "sudden death" will be played. A player returns to each chukker on a different pony, although he may rest a pony for a chukker or two and play the same pony again.

Start: The four players of each team line up in the middle of the field, facing the side boards. The umpire rides toward them, throws the ball between them, and the game play begins. Play is resumed in the same way after each goal, with teams changing goals.

Play: The players strike the ball with the side of the mallet, attempting to drive it toward the opponents' goal and through the goal posts.

Fouls and Penalties: The game is controlled by 12 general rules, covering everything from the size of the ball to the colors of team shirts, and 24 field rules setting regulations, from the use of sharp spurs to the actual play. When a foul has been committed, penalty shots are awarded by the umpires to the team which has been fouled. This can be as a result of any of a number of infractions of the rules by a member of the opposing team, or the team itself. The more severe the foul, the more severe the penalty. The most important rules in polo are those concerning the safety of men and horses. Chief of these are the crossing and riding-off rules. No player may cross the line of another in going for the ball, and the last man to strike the ball has the "right-of-way". Others may legitimately "ride him off", however. This means impinging, pony to pony, on a converging course in the manner of a shoulder charge in football.

Penalty No. 5: A free hit at the ball from where the foul occurred in the case of an inadvertent foul hook or from midfield. The fouling team must be 30 yards away from the ball, while the team which has been fouled can be anywhere.

Penalty No. 4: A free hit, 60 yards from the defended goal. The defenders cannot be closer than 30 yards from the ball, but can protect the goal.

Penalty No. 3: A free hit from 40 yards from the opponent's goal, with the team that has fouled behind the end line, and the goal undefended.

Penalty No. 2: A free hit from 30 yards from the opponent's goal, with the team that has fouled behind the end line, and the goal undefended.

Penalty No. 1: The fouled team is awarded a goal. The teams do not change playing direction.

Safety: A safety occurs when a ball is hit, or deflected behind the back line by a player of the defending team. The penalty for a safety is a free hit by the offensive team, 60 yards from the goal, at a point in line where the ball crossed the back line
Over the End Line: When an attacking player drives the ball over the end line outside the goal posts, a defending player puts it in play by a free hit from the point where it went out; in no case, however, may the hit be made closer than twelve feet from a goal post. Should a defensive player, in an attempt to prevent a goal, cause the ball to go over his own end line, a safety is called.

Goal: Any time a ball crosses the line between the goal posts, it is considered a goal regardless of whether a horse or a mallet causes the ball to go through. In order to equalize wind and turf conditions, the teams change sides after every goal scored.

Throw-In: A chukker begins and many plays resume with the umpire bowling the ball between the two ready teams.

Positions: Each of the four players plays a distinctly different position. Since polo is such a fluid game, the players may momentarily change positions, but will try and return to their initial assignment. No 1 is the most forward offensive player. Usually selected for his accurate shooting at the goal. No 2 is also offensive, but plays behind No 1, attempting to pass the ball up to him. Usually chosen for his quickness and dexterity. No 3 is the pivot player between offense and defense. He is the play maker and usually the longest hitter on the team. His duty is to pass the ball to his forwards. No 4, or the back, is the most defensive player. His duty is to turn the ball back upfield to his teammates. He is usually selected for his ability to hit backhanders and ride-off his opponents.

Bump Or Ride-Off: This occurs when two riders make contact and attempt to push each other off the line of the ball so as to prevent the other from striking the ball. The horses are the ones intended to do the pushing, although a player may use his body as well, but not his elbows. The angle of the bump must be slight so as not to be dangerous to the rider or horse.

Tail Shot: Hitting the ball behind and across the horse's rump.

Hook: A player may spoil another's shot by putting his mallet in the way of the striking player's mallet. A cross hook occurs when the player reaches over his opponent's mount in an attempt to hook; this is considered a foul.

Knock-In: Should a team, in an offensive drive, hit the ball across the opponent's endline, the defending team resumes the game with a free hit from their endline. No time out is allowed for knock-ins.

Out Of Bounds:When a ball crosses the sideline or goes over the sideboards, it is considered out of bounds and the umpire throws in another ball between the two teams at that point. No time out is allowed for an out-of-bounds ball.

Time Out: An umpire calls time out when a foul is committed, an accident occurs, or at his own discretion. A player may only call time out if he has broken tack or is injured. No time out is allowed for changing horses or replacing a broken mallet, although a player may do so at any time.

Third Man: The referee sitting at the sidelines. If and when the umpires on the field are in disagreement, the third man makes the final decision.

Sideboards: A nine to eleven inch board along the side-lines only. Sideboards are optional.