Atlantic League to Test New Mound Distance, DH Rules for MLB over Summer

The Atlantic League will be the guinea pig for MLB again this summer, with the independent organization set to test new rules in the second half of its season, MLB announced Wednesday (h/t ESPN's Jesse Rogers).

Those changes include moving the pitching rubber back one foot (to a distance of 61 feet, 6 inches) as well as a "double-hook" rule, which will eliminate the designated hitter when a starting pitcher comes out of the game.

The Atlantic League was supposed to move its mounds back two feet for the second half of 2019, but per Rogers, that idea "was abandoned before it began."

The MLB mound was last moved in 1893, when the National League added five feet to the distance between the plate and the hill.

The aim is to give hitters more time to react; MLB strikeout rates have risen in 15 straight years.

In 2019, MLB set a record for strikeouts for the 12th year in a row, with 42,823 players heading back to the dugout, per Rogers.

"We expect to learn a great deal about the impacts of such a change and whether an adjustment to this critical field dimension is worth potential future consideration at other levels of professional baseball," MLB consultant Theo Epstein said in the statement.

The "double-hook" rule will be in place throughout the season, which begins May 27. That rule was adopted to encourage teams to keep starting pitchers going later into games.

"Major League Baseball is being more aggressive than they've ever been in experimenting with new rules," Milwaukee Brewers manager Craig Counsell said Wednesday (via Rogers). "We have to wait and see what the effects are. I'm not sure how it's going to affect the game."

The Atlantic League is still using an automated umpire to call balls and strikes, which it has been doing since 2019. Most Low-A Southeast League games will also use that Automated Ball-Strike System in 2021.