MLB Outlines 2023 Minor League Rules Changes

In a memo distributed among its executives on Tuesday, Major League Baseball outlined a series of rules changes to be used during the 2023 minor league season. Some—like the pitch clock, larger bases and restrictions on defensive positioning—are tweaks to changes that have been put in place in previous seasons in the minor leagues and have been adopted in the big leagues. 

Others, like the use of PitchCom and baseballs designed to help pitchers get better grips, are new to the minors. 

Here are the changes as outlined in the memo:

PITCH CLOCKS: As in 2022, pitch clocks will be in play at all full-season levels (but not in the complex leagues in Arizona, Florida or the Dominican Republic). The differences from 2022 to 2023 are small.

Between pitches with the bases empty, the MiLB pitch clocks will be set to 14 seconds. That’s a one-second shorter difference from the big leagues. 

Between pitches with runners on, Triple-A clocks will be set to 19 seconds. From Double-A on down, the clocks will be set to 18 seconds. In the big leagues, that figure is 20 seconds.

There is no difference in between-hitter and between-inning timing in the big leagues and the minors; all levels will have 30 seconds and 2 minutes, 15 seconds, respectively, in those situations. The between-inning timer will begin as soon as the final out of the preceding half-inning is recorded. Previously, the timer would not start for a new pitcher until he had exited the bullpen area. 

Batters will be required to be “in the batter’s box and alert to the pitcher” with eight seconds remaining on the timer. This change shaves a second off of the rules from 2022 and aligns with the big league standard. 

Unlike 2022, there will be no ease-in period during the 2023 season. The rules will be enforced immediately upon Opening Day. 

The only exceptions will be for major leaguers on rehab assignments. In those cases, the clocks will be enforced to the MLB standards.  

PICKOFFS AND STEP-OFFS: Pitchers will be limited to two disengagements—pickoffs, pickoff attempts or any other disengagement from the rubber with runners on base. This count will remain the same even if a runner advances or is picked off during a plate appearance. In the big leagues, the disengagement count will reset if a runner advances during a plate appearance. 

BASE SIZE: The 18-square inch bases will return in 2023. In the first half of the season, the bases will be positioned in their normal fashion. The league will gauge the level of stolen base activity, however, and reserves the right to move second base entirely within the baseline, which would reduce the distances between first and second and second and third base. If enacted, teams with turf fields could be exempted from such a change depending on the practicality of de-anchoring and re-anchoring the base.

DEFENSIVE RESTRICTIONS: All full-season levels will require all four infielders to be within the bounds of the infield (i.e. nobody in the outfield) with two infielders apiece on either side of second base. Infielders may not shift sides—the shortstop cannot move to second base and vice versa—unless there is a substitution for a defensive player other than the pitcher. 

The Florida State League will also see the return of the “pie slice” rule, which kept middle infielders from bunching up the middle. This move is designed to open that area of the infield for base hits. 

PITCHCOM: Triple-A teams will have PitchCom available during the season. It will not be available at Double-A or below. Teams will be provided one transmitter and four receivers. The only individuals allowed to wear PitchCom receivers are the active pitcher and catcher and a pitcher warming up in the bullpen. Only the catcher is allowed to use the transmitter during play. 

 

AUTOMATIC BALL-STRIKE: The ABS systems will be in use in Triple-A and the Low-A Florida State League. Some games will be Full ABS, which means balls and strikes will be solely determined by the computer system. Others will have ABS Challenge games—which were in use during 2022 Arizona Fall League games played at Salt River Fields. 

In these games, balls and strikes are determined by the home plate umpire but each team can challenge a call to the ABS system. Each team gets three challenges–which may only be initiated by the pitcher, catcher or hitter—per game. However, if a challenge is successful, a team keeps that challenge for later in the game. Appeals to a challenge must be made within two seconds of the home plate umpire’s call. 

Teams will also be issued iPads which allow them to see ball-strike results in real time, as determined by the ABS system. This will allow players to see why certain pitches were called balls or strikes by the ABS system. 

In Triple-A, the first three games of each series will be played using full ABS. The latter three games of a series will use the ABS Challenge. 

These guidelines will begin in the Pacific Coast League on Opening Day. To ensure systems are working properly, the guidelines in the International League will begin on April 19. 

The ABS strike zone width is calculated as 17 inches wide (the same as home plate). Its height is set at 27% and 51% of each hitter’s reported height. The height parameters are the same from what was in play in the second half of the 2022 Triple-A season, but the width has been shortened by an inch on either side of the plate in an effort to reduce strikeouts. 

The league reserves the right to monitor and adjust the width of the ABS strike zone as necessary. 

Daytona will be the only exception to the ABS rule in the FSL. The strike zone in that league will be unchanged from 2022, but slightly different to what was enforced for height. In the FSL, the height of the strike zone will be set at 52.5% and 27% of a batter’s reported height. 

The memo also notes that the league is exploring a strike zone with “rounded corners” and will put such a system in play sometime in the first half of the FSL season, once it can be properly displayed in all necessary formats. Teams will be informed before the change is made. The reasoning behind the rounded corners is to reduce strikeouts and encourage more balls in play. 

All batter heights for the purposes of the ABS will be determined by a group of independent personnel and will be recorded while the players are not wearing shoes or cleats. 

ENHANCED GRIP BASEBALLS: The memo distributed to club personnel outlines that the league began working in 2021 with Dow Chemical in order to establish an alternative to the Delaware River mud currently applied to baseballs. These baseballs are manufactured by Rawlings and, according to the memo, are “identical to the baseballs that will be in use during the 2023 Major League season.”

These Enhanced Grip Baseballs will be in play in the Southern League from Opening Day through July 13. Games afterward will be played with traditionally mudded baseballs. Clubs in the Eastern and Texas Leagues will use standard Minor League baseballs.