The pitch is a rectangular area of the ground 22 yards (20 m) long and 10 ft (3.0 m) wide. The Ground Authority selects and prepares the pitch, but once the game has started, the umpires control what happens to the pitch. The umpires are also the arbiters of whether the pitch is fit for play, and if they deem it unfit, with the consent of both captains can change the pitch. Professional cricket is almost always played on a grass surface. However, in the event a nonturf pitch is used, the artificial surface must have a minimum length of 58 ft (18 m) and a minimum width of 6 ft (1.8 m).