According to The Athletic, changes in how Major League Baseball evaluates umpires have resulted in fewer called strikes on the edge of the zone through the first month of the 2025 season.
The change was made as part of the league’s new labor agreement with the umpires’ union, signed in December.
According to The Athletic, the umpire evaluation process has undergone the following changes:
For the past two decades, umpires were working with a “buffer zone” that gave them 2 inches of leeway — on all sides of the plate, inside and outside the strike zone — when they were graded on how accurately they called balls and strikes.
Now, however, that buffer zone has shrunk, from 2 inches on all sides to just three-quarters of an inch on all sides, inside and outside the strike zone, according to league sources briefed on the change but not authorized to discuss the matter publicly. An MLB official confirmed that the buffer zone had decreased in size.
“We informed the GMs and Field Managers that we were seeking this change during the offseason, and again informed the Clubs when the umpire CBA was ratified,” the league’s representative told The Athletic. “Overall ball-strike accuracy in 2025 is the highest it has ever been through this point in the season.”
According to Statcast data, ball/strike calls have been more accurate in the early going this season than at any time since Statcast’s inception in 2015. This year, just over 88% of all ball/strike calls were correct.
In 2016, it was below 84%. Since pitch tracking began in 2008, umpires’ accuracy of ball/strike calls has steadily improved year after year.
Several players told The Athletic that they believe the strike zone is tighter this year. Even though the zone is tighter, it has not increased offense.
The league as a whole was hitting.242/.316/.392 and averaging 4.34 runs per game heading into play Thursday. This almost exactly matches last year’s.243/.312/.399 line and 4.39 runs per game average.
The difference in ball/strike call rates between this year and last year amounts to less than one pitch per game. When the MLB competition committee meets next, they will likely discuss the change in how umpires are evaluated and its impact on the game. The competition committee is comprised of six owners, four players, and one umpire.
