Third umpire

In international cricket matches the third umpire (or TV Umpire) is an off-field umpire who makes the final decision in questions referred to him by the two on-field umpires. Television replays are available to the third umpire to assist him in coming to a decision. An on-field umpire can, at his own discretion, use a radio link to refer any close decision concerning dismissals (catches, runouts or stumpings) or boundaries to the third umpire.

The third umpire was conceptualized by former Sri Lankan domestic cricketer, and current cricket writer Mahinda Wijesinghe and debuted in Test cricket in November 1992 at Kingsmead, Durban for the South Africa vs. India series. Karl Liebenberg was the third umpire with Cyril Mitchley the on-field umpire, referring the run-out decision in this match. Sachin Tendulkar became the first batsman to be dismissed (run out) by using television replays in the second day of the Test scoring 11.

In the case of a run out or stumping, a batsman may be declared "out" if the wicket is 'put down'. The wicket is down if a bail is removed from the top of the stumps or a wicket is struck out of the ground, whether by the ball, the bat or the striker's person. If the batsman is caught between the two popping creases and the wicket is put down, the batsman is declared out. In most cases, the event occurs in a fraction of a second. If the field umpires are unable to accurately come to a decision on the dismissal of a batsman, the umpire requests the third umpire to ascertain whether the batsman had made it home. The third umpire then looks at various TV replays from different angles and comes to a conclusion by pressing the appropriate signal. Originally decisions were conveyed in traffic light style (a red light indicating a batsman's dismissal, a green light not out); it is now common practice to display the decision via the large screen scoreboard, if available. If the umpire is unsure if a batsman is out or not, due to lack of conclusive evidence, the usual procedure is to acquit the batsman, known in cricketing parlance as "the benefit of the doubt".

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