About the game
Each match is controlled by two umpires. Each umpire controls half of the pitch and works cooperatively in the middle part of the pitch.
For bad or repeated offences by players, an umpire can show them a card. A green card is a warning. A yellow card means the player is suspended from the game for a minimum of 5 minutes or the time the umpire decides depending on the nature of the offence. A red card is for a very serious offence and means the player is suspended for the remainder of the match. If a player is suspended temporarily or permanently, their team plays with fewer players.
At world level competitions where the facilities are available, a team playing or the umpires themselves can refer a decision to the video umpire who can use slow motion replays to advise the umpires on the pitch of the correct decision.
By International Hockey Federation