Pacing rules to go into effect in Minor Leagues

Minor League Baseball announced a series of rule changes relating to pace of play Wednesday that will be applied to all levels below the Majors in 2018. Chief among the changes, which were created in partnership with Major League Baseball, are rules intended to reduce the number of pitchers used in extra innings, as well as a rule reducing the number of mound visits that will mirror the limits to be implemented in MLB games this year.
All Minor League innings past the requisite nine frames this season will begin with a runner on second base, in a manner similar to what was used in last year's World Baseball Classic. The runner will be the player previous to a team's leadoff hitter for that inning in the batting order. Teams may substitute a player with a pinch-runner, but the player removed will not be allowed to return to the lineup.
Similar to big league games, mound visits will be limited to six per team at the Triple-A level. Double-A clubs will be allowed eight mound visits per game, while Class A Advanced teams will be allotted 10 visits. There will be no mound visit restrictions for Class A Short Season and Rookie-level teams. Clubs will be given an additional mound visit for each subsequent extra inning.
Triple-A and Double-A games have featured 20-second pitch clocks since 2015, but that clock will be wound down to 15 seconds when the bases are empty in '18. The clock will go back to the original 20-second countdown for pitchers once a runner reaches base. The timer begins when the pitcher receives the ball from the catcher, and it stops when he begins his windup or comes to the set position.