"Since Beijing (2008 Games venue), the possibility for a team to request a referral has been included and so London will see this for the first time at an Olympics. Each team is allowed one team referral, which must be made through the match umpire. This can occur at any time during a match, including extra time in classification matches, but not during shoot-outs. Only umpire referrals are permitted during a shoot-out," the FIH website said.
"Team referrals are restricted to decisions within the 23 metre areas relating to goals, penalty strokes and penalty corners. Penalty cards may not be the subject of a team referral," it added.
Pointing out that in addition the umpires can also ask for referrals as is already the case since the Beijing Games, the website said that a video umpire would be in operation for all the men's and women's matches held "on the main competition pitch."
"Video umpire was first used in the Olympics in Beijing. At that time, it was only the umpires that could initiate a referral. These umpire referrals will still be in operation in London, whereby the umpires can refer decisions to a video umpire when they are not convinced that they have made or can make the correct decision about awarding or disallowing a goal. This includes whether a breach of the rules has taken place within the attacking 23 metre area in the play leading to the goal."
Any player on the pitch at the time of the incident can request for a referral by using the 'T' sign to alert the umpire who will then ask the video umpire to ask for the replays "from the available camera angles and gives the recommendation to the match umpire. The final decision always rests with the match umpire."
"If a team referral is upheld, the referring team retains its right of referral." (MORE)