Shrinkage! Why MLB Players Got Shorter Over The Winter
In the era of robot umpires in baseball, being short is finally a competitive advantage.
How did Tampa Bay Rays OF Gavin Lux shrink three inches over the winter?
Lux went from being listed as a 6'2" second baseman as a member of the Cincinnati Reds in 2025 to a 5'11" utility guy for the Rays, his new team. That's not a misprint. That's the result of Major League Baseball introducing the Automated Ball-Strike (ABS) system.
With a computer now calculating a strike zone for each player and tracking pitches down to the millimeter, measuring the correct height of players became a major offseason project for MLB.
In February, the players were brought into a lab and told to take off their shoes. It was finally time to measure their exact height.
The rules for that measurement included:
- No shoes
- No hats
- Knees exposed
- Heels together
- Back against the wall
- No slouching
When the smoke cleared, Lux was 5'11".
League officials took two height measurements of each player, according to MLB reporter Adam McCalvy. If those measurements were off by more than two millimeters, another measurement was made and then an average was calculated.
MLB players who have been subjected to ABS-related ‘shrinkage’
- Alec Bohm: 6'5" to 6'4"
- Bryce Harper: 6'2" to 6'1"
- Edmundo Sosa: 6'0" to 5'11"
- Zach McCambley: 6'2" to 6'1"
- Bryson Stott: 6'1" to 6'0"
Harper has gone from 6'3" in 2024 to 6'1" this season.
As for a player to keep an eye on who keeps getting shorter by the year, look no further than Alex Bregman. He was listed at 6'0" with the Astros. Last year, with the Red Sox, he was 5'11".
Now?
The Chicago Cubs have Bregman measured at 5'10".
While the players were being measured down to the millimeter, teams have been creating their strategy for when to challenge a call.
"I think we’ve got ideas, but it’s not set in stone yet," Padres manager Craig Stammen told Fox Sports in February. "I’ll tell you this: It won’t be a free-for-all. We’ll try to be as strategic as we can with it."
Each team will get two challenges. If the challenge is successful, the team keeps its challenge. The challenge must be made within two seconds of the call. The challenge has to be made by the pitcher, catcher or hitter without help from the dugout.
Here's a twist on the ABS: An umpire can overrule a challenge if he (or she) determines the pitcher, catcher or hitter was aided by a defender, runner or the dugout.