The Weekly Rotation • 3/25/2026
What Spring Training Taught Us About ABS
MLB's first full spring of challenge-era ABS showed real team separation, real umpire variance, and early evidence that challenge timing may matter more than raw volume.
By Colby Reichenbach
Spring was supposed to introduce ABS. Instead, it gave us the first usable sample of how clubs might actually live with it.
Across 451 final Spring Training games, MLB clubs used the ABS challenge system 1,913 times. The overall overturn rate settled at 52.9 percent. More important, 443 of those 451 games, just over 98 percent, featured at least one challenge. That is enough usage to stop treating ABS as a novelty. By the final week of camp, the challenge system was showing up in normal game flow, and once that happened the more interesting question was no longer whether teams would use ABS. It was how they would use it.
My read from the spring is straightforward: the first meaningful ABS sample already suggests that clubs are separating into different operating styles. Some teams challenged often. Some challenged early. Some held more of their challenge traffic for later innings. And the data hints that the most interesting distinction may not be raw volume at all, but what kind of challenge environment a club is willing to enter.
That does not mean spring solved ABS. It means the sample is large enough to show directional behavior, even if it is still too small to make permanent claims about team quality, organizational superiority, or umpire talent.
derived metric
Spring Produced Real ABS Identities
At the league level, spring was not tentative.
- 451 final spring games
- 1,913 tracked challenges
- 1,012 overturned calls
- 52.9 percent overall overturn rate
- 4.24 challenges per game
- 443 of 451 games with at least one challenge
That volume matters because a system used in more than 98 percent of games stops being hypothetical. It becomes part of the baseball environment. Once that happens, differences in team behavior become meaningful.
The first clear split was simple challenge volume. The Yankees led the spring with 101 challenges. The Twins followed with 89, then the Rockies with 84, the Guardians with 78, and the White Sox with 77. On the lower end of the spring sample, the Tigers finished with 40, the Diamondbacks with 44, and both the Mets and Dodgers with 47.
That alone does not prove anything strategic. More aggressive usage could reflect process, roster mix, spring experimentation, or simple noise. But it does establish that clubs were not approaching ABS uniformly. Some treated it like a regular part of their decision surface almost immediately. Others were materially more selective.
The second split is more revealing. Teams were not just separating by how often they challenged. They were separating by when those challenges appeared.