Major League Baseball has gone ahead with its planned rules changes for this season

They include the requirement a pitcher must face at least three batters or end the half-inning, unless he is hurt.

Position players are prohibited from pitching through the ninth inning unless the player's team is winning or losing by six or more runs when he takes the mound.

The injured list and option recall minimum period for pitchers will increase from 10 days to 15.

Managers' time to challenge a play with a video review has been cut from 30 seconds to 20.