Fourth umpire

Fourth umpire sometimes referred to as the reserve umpire, is a cricket official. For all international matches a fourth umpire is required to perform duties like bringing on the new ball, carrying drinks on to the field for the umpires, checking the batteries in the light meter and observing the pitch during the lunch and tea intervals to make sure there is no interference. The Fourth umpire will take over the Third umpire duties if something happens to one of the onfield umpires, as the rules state the third umpire will take over on field duties.