MLB, Atlantic League Announce Several Significant Rule Changes

Image credit: (Photo by Carl. D Walsh/Portland Press Herald)

Major League Baseball and the Atlantic League announced several rule changes Friday ahead of the 2019 season, cementing MLB’s use of the independent league as a testbed for significant experiments.

Among the changes: The Atlantic League will use Trackman to call balls and strikes (more affectionately known as robo umps), push the mound back to 62 feet, six inches, eliminate shifts, implement a three-batter minimum for relievers and several more.

Baseball America first reported the rule changes in late February.

Here is the full list of changes:

Computer assisted strike zone
No mound visits by players other than pitching changes/injury
Pitchers face minimum of 3 batters or end of inning.
Increase bases by 3 inches (to 18 inches)
Two infielders must be on each side of second base when a pitch is thrown
Time between innings will be cut from 2:05 to 1:45
The mound will be moved back by two feet in the second half of the season

According to the league, MLB is choosing to implement the mound move in the second half of the season because it can “more precisely measure the impact” of the decision by comparing first half to second half.

And as far as increasing the base size? The league said the decision is two-pronged: It should increase player safety by allowing fielders and runners more room on the base, and it hopes batting average on ground balls and stolen base percentage will slightly improve by making the bases closer together.

MLB and the Atlantic League first announced their three-year agreement in late February. It’s a unique arrangement, and one that would’ve been nearly impossible to do at either the minor league or fall ball level. Major League Baseball can now harvest three years of data from the Atlantic League, which is filled with ex-MLB talent. Last year, 32 Atlantic League players later signed contracts to return to affiliated ball.

To read more about the agreement and potential impact of such changes, click here.