NEW YORK (AP) — Teams will be limited to three trips to the mound by managers, coaches and catchers during a game, except for pitching changes, under experimental speedup rules to be used during the Arizona Fall League.

The pace of game committee established last month by baseball Commissioner Bud Selig announced a series of initiatives Wednesday that will be tried in the AFL, which opens Oct. 7 and runs until Nov. 15. The three-trip limit will apply even if a game goes to extra innings.

The average time of nine-inning games in the major leagues was a record 3 hours, 2 minutes this year, up from 2:33 in 1981.

Pitches will be eliminated during intentional walks, and a hitter will be required to keep at least one foot in the batter’s box throughout each at-bat, unless there is a foul ball, wild pitch or passed ball — or if a pitch forces him out or the umpire grants “time.”

In games at Salt River Fields, a 20-second clock will be posted in each dugout, behind home plate and in the outfield to prevent pitchers from taking too much time. If a batter steps out of the box during the 20-second period that ends with the start of the pitching motion, the pitcher can throw. The umpire may call a strike if the batter has not been granted time. The clock will start when the pitcher has the ball or, after a foul, when the umpire signals “play.”

Normally, rule 8.04 says a pitcher should pitch within 12 seconds of receiving the ball when the bases are empty, and umpires may call a ball for a violation. But that rule is rarely enforced.

Hitters will be directed to get in the batter’s box by the 1:45 mark of the 2:05 break between innings, and violations may be punished by strike calls. The maximum time for a pitching change will be 2:30, including changes before the start of an inning.

In addition, the MLB video review system that started this year will be in use and will include experimental rules regarding scope, initiation and time limits.