Third Umpire Duties : The third umpire is also known as on off-field umpire who usually gives his decision when the on-field umpires are unsure. The third umpire looks at various TV replays from different angles and comes to a conclusion by pressing the appropriate signal. The field umpire can use his discretion to refer a close decision to the third umpire regarding the dismissal of a batsman, catches or boundaries via a wireless set or a signal system. Third umpire conveys his decision through radio link and television replay. A red light indicates that the batsman is out and a green one otherwise.