Rule 21 · USPA Rulebook 2026
How play is stopped
The situations in which the umpire whistles: safety, foul, broken ball, injuries and falls, injured horses, broken tack, lost helmet, lodged ball, end of period, suspension and an accidental whistle.
Only the whistle stops play
Play shall be continuous until play and the clock are stopped by the Umpire blowing the whistle in one of the following situations:
Safety
Ball Hit Across End Line (Safety). If a player hits the ball across that player’s own end line, either directly or after glancing off that player’s own mount, a goal post or the side boards, the Umpire shall stop the game and call a Safety (Penalty 6) unless the ball strikes another player, an opposing player’s mallet, or another player’s mount before crossing that end line. A player is considered to have “hit” the ball if the ball merely touches the mallet. This is true even though the player may have been swinging in the opposite direction or not swinging at all.
Foul and advantage
Foul called.
Any violation of the Rules constitutes a foul and the Umpire may stop the game by sounding the whistle.
Calling the advantage: The Umpire may also elect not to stop play by calling a foul, or to briefly delay the stoppage of play for a foul, if the Umpire deems it to be in the best interest of the game or if interrupting the game and awarding a penalty would result in a disadvantage to the team fouled. Generally, if the Umpire delays blowing the whistle to assess whether the fouled team would be disadvantaged by a foul call, he or she should make that assessment immediately after the next play.
Verbal cues: To facilitate compliance with the rules and promote game flow, the Umpires may use verbal cues when time and proximity permits to inform players of potential rule violations, but they are not required to do so, and they should never coach or instruct the players. Examples of acceptable verbal cues include, but are not limited to: “Clear,” “Use it,” “That’s your tap,” and “Blue 3, you’re offside.”
In the event of a foul being called when play is already stopped, such as a violation of Rule 30 or 33, the Umpire may so signal by: a) again sounding the whistle; or b) displaying a yellow or red card, at the option of the Umpire.
Damaged or buried ball
Damaged, Buried Ball. If the ball becomes damaged to the extent it is unplayable by being chipped, broken, or trodden into the ground the Umpire shall stop the game. What is a chipped, broken, buried, or unplayable ball shall be within the sole discretion of the Umpire. If the ball is minorly chipped or broken, the Umpire should not stop the game until it is in such a position that neither team is favored. In the case of a broken ball, the largest piece shall be played unless the Umpire stops the game.
Injured player
Injury to Player. If a player is injured, the Umpire shall stop the game, and the player shall have 10 minutes within which to recover, provided, however, that the Umpire(s), in their discretion, may grant additional time, and that no player who has been rendered unconscious shall be allowed to resume play in any game that day. If, and when, during this interval the injured player is able to resume play or an eligible player is substituted, the Umpire shall continue the game. The game shall be continued not more than 10 minutes after it was stopped because of the injury unless the injured player’s treatment on the field requires additional time to remove the player from the field or the Umpire has granted additional time. There shall be no subsequent time-outs for a recurrence of the same injury.
Player falls
Player Falls Off. If a player falls off, the Umpire shall stop the game when the ball is in neutral territory (i.e., as soon as neither team will be deprived of an imminent opportunity to score a goal). If, however, the player, in the opinion of the Umpire, may be injured, or in jeopardy of being injured, the Umpire shall stop the game immediately. What constitutes a fall shall be left to the discretion of the Umpire.
Fallen or Injured Mount:
Injured or distressed horse
The primary responsibility for the welfare of each mount lies with the player who rides it. During a break in play, or exceptionally during play, a player may inform the Umpires that his or her mount is injured or distressed, in which case they should stop play immediately. If:
The Umpires determine that the mount is visibly injured or distressed – the Umpires should announce “ALL MAY CHANGE.” The mount in question must be led off the field or taken off by horse ambulance. Play will be restarted with a throw-in when the player with the injured mount has returned on another mount. Any unwarranted delay on his or her part will be penalized. The excused mount may not play again in the game.
The Umpires determine that the mount is not visibly injured – the Umpires may instruct the player to change by leading the horse off the field by the shortest line to the side of the field. No other player on his or her team may change mounts. Play will resume as soon as the mount is off the field. The excused mount may not play again in the game.
Courtesy change
The Host Tournament Committee or Umpires have the authority to stop any injured or distressed horse from playing. When heat or humidity is extreme, or after an extended period of inclement weather that has prevented the teams from properly preparing their horses, to be determined by the Host Tournament Committee or the Umpires in their discretion and communicated to the teams before the game begins, the Umpires may allow one courtesy horse change per period for all players on both teams when the ball is out of play or at a neutral play. Ideally, the Umpires will allow any such courtesy horse change after three minutes have elapsed in the period by announcing “ALL MAY CHANGE – COURTESY CHANGE, ONE MINUTE.”. One minute shall be allowed for players to change horses. Play will be restarted with a throw-in, penalty, free hit or knock-in, as the case may be, after one minute has elapsed. Any unwarranted delay by either team will be penalized. When the Host Tournament Committee or Umpires allow one courtesy change per period pursuant to this provision, the teams shall be required to provide each Umpire two horses for any game lasting four periods or more.
Horse falls
Mount Falls: If a mount falls, (i.e., its body touches the ground) the Umpires should stop play immediately and, if the player wishes to remount, ensure that the mount is trotted and examined for soundness. If the mount is sound and there is no evidence of injury, the player may remount but otherwise he must change mounts in accordance with subparagraph 21.f(1)(i), above.
Player's time-out for a horse
Player Time Out for Injured Mount: If a player asks for time out for an injured or fatigued mount, the Umpire(s) may, in their discretion, stop the game immediately or at a neutral play. The player shall have 5 minutes to change mounts and the injured mount may not return to the game. No player on that player’s team may change mounts until after play has resumed. If the Umpire notices that a team member or members have changed mounts, an appropriate penalty will be awarded to the opposing team and play will resume immediately.
Returning an excused horse
If a player returns a mount to play after it has been excused under provision 21.f(1), 21.f(3) or 21.f(4), the penalty shall be forfeiture. If, within 24 hours after a game, the Umpire(s), a Referee, or the Host Tournament Committee is presented with conclusive physical evidence (including, but not limited to, photographic or video evidence) that a player returned a mount to play after it was excused under one of these provisions, and the violation was not detected during the game, the penalty shall be forfeiture. Unlike many other penalties which the Umpire(s) may elect not to exact, this penalty (forfeiture) must be exacted, whether during or after a game.
Broken tack or equipment
Broken Tack or Equipment:
The game will be stopped immediately in the interest of safety for tack which presents a danger to any player or horse such as a broken girth or broken martingale if the end trails on the ground, broken rein if single, broken or loose bit, broken curb chain or loose bandages or boots. The Umpires may allow the player to rectify the problem immediately on the ground if it can be done quickly. In games or events with an upper handicap level of 6 goals or less, to be determined by the Host Tournament Committee or the Umpires in their discretion and communicated to the teams before the game or event begins, the Umpires may allow the affected player a maximum of five (5) minutes to rectify the problem or change mounts if it cannot be rectified quickly on the ground. In all other games or events, the player must leave the field of play and play will be restarted as soon as the player has done so, unless the tack has been broken by contact with another horse in which case the start of play will be delayed for five (5) minutes or until his or her return, whichever occurs first.
If, in the Umpire’s opinion, damaged or broken equipment may pose a risk to any player or mount, the Umpire shall wait to stop the play at some neutral play, unless he considers the damaged equipment may immediately interfere with the play or endanger a player(s) or mount(s), in which case he shall stop play immediately.
Lost helmet
Lost Helmet. If a helmet falls off, the play shall be stopped as soon as possible when the play is in a neutral position.
Lodged ball
Lodged Ball. If the ball becomes lodged against a player, a mount or equipment, in such a way that it cannot be dropped immediately, the Umpire shall stop the game and the ball shall be considered dead at the point where it was first lodged.
End of period
Period Ends. The Umpire shall stop the game at the end of each period.
Suspension
Suspension of Game. The Umpire may suspend the game in the event of darkness, inclement weather, or any other reason which the Umpire(s), Referee and Host Tournament Committee believe to be in the best interest of the game.
Accidental whistle
Inadvertent Whistle. In the event of an inadvertent whistle stopping play there shall be a throw-in toward the boards or sideline at the point at which play was stopped, except in circumstances when Rule 22.h (Fair Play Possession) applies.
The game is stopped only by the Umpire’s whistle. Because the Umpire is responsible for the safe conduct of the game according to the Rules, the Umpire has a great deal of discretion as to whether or when to stop play. Fouls involving safety of player or mount should be called at the instant they occur. The Umpire should not elect to delay the call of dangerous fouls. An infraction involving mechanics or “advantage” may be a non-call, or delayed call, at the Umpire’s discretion. When a foul occurs at or slightly after the horn ending any regulation period but the final regulation period, the penalty should be executed at the beginning of the next period. When a foul occurs at or slightly after the horn ending the final regulation period, five seconds should be put on the clock and the penalty executed. An unsportsmanlike conduct penalty assessed between periods shall be executed at the beginning of the next period.
Red #1 hits wide of goal and is a little slow returning to the field. As Blue #3 knocks in, Red #1 is at about the 25-yard mark. The Umpire may elect not to call this foul if Red #1 is not endangered or taking advantage of his incorrect positioning. The Umpire’s whistle sounds and a foul is announced against Blue #1. Blue #3 protests the call excessively. As play is already stopped, the Umpire may signal a “dead ball foul” on Blue #3 either by sounding the whistle again, or by displaying a yellow or red card. The horn blows one second before Red #1 makes a dangerous crossing foul in front of Blue #4. The Umpires should award an appropriate penalty to Blue. After the period has ended and while riding back to the sidelines, Blue #2 informs the Umpire that he needs glasses. A yellow card should be displayed and the next period started with a penalty. Blue #4 knocks in and rides to follow up. Red #2 circles to Blue’s left and is slightly ahead. Blue, anticipating that Red will interfere with his ROW to the ball, checks to avoid a possible collision. Red pulls out and gives Blue passage to the ball. The trailing Umpire sees the minor infraction but holds up on the whistle to see how the play will develop. Blue #4 hits a long shot to Blue #2, who hits a long shot to goal. This non-call by the Umpires is justified because Red did not interfere with Blue’s play and did not disadvantage the Blue Team. Red #1’s girth breaks during a hard turn. Red #1, in traffic, is in danger of falling and no longer has control of his mount. The whistle should be blown to stop play, regardless of the location of the ball. Play is resumed with a throw-in after repairs have been made. Blue #4 breaks a stirrup leather. He is out of the play and holds his mount under control. The game should continue until the ball is out of play at which time the whistle should sound. Red #3 hooks an opponent and drops his mallet. Red plays on without a mallet until the ball goes over the boards and then asks for time to retrieve the dropped mallet. Time should not be granted. Red may play with, or without, a mallet, but must procure a new one on his own time. Red #3 breaks a stirrup hanger. When play stops, Red #3 requests time out and asks the Umpire if he can change horses rather than make repairs. Permission may be granted if the change can be made more quickly than the repair Blue #1 loses a curb chain. As his groom makes the repair, Blue rests in a lawn chair catching his breath. The repair is made and Blue still rests. The Umpire should call for a lineup. A player is permitted only necessary time up to 5 minutes. Red #2 asks for, and is granted, time out for tack repair. He does not ask permission to change mounts. When Red returns to the field, he has changed horses. This is a violation of Rule 21.g. The whistle, or a yellow card, should signal the “dead ball” foul, and the appropriate penalty applied. After a particularly hard bump, Blue #3 asks for time out to check his mount. The mount trots out sound, Blue #3 remounts, and play continues. If Blue #3 elects to change mounts, the time out will be extended but the mount may not return to the game. Red #3’s mount falls after a collision. The Umpire’s whistle should sound immediately. Red #3 may trot out the horse and remount, or change. If he elects to change, the mount may return to the game. Blue #2’s mount is tired after a long run. If Blue requests time out to change, the mount may not return to the game. If Blue changes as the game proceeds, the mount may be played later.