The robots have arrived at spring training. And they’re right more than half the time.
MLB’s new Automated Ball-Strike Challenge System is live in exhibition games this year, giving us our first real look at how the technology will work when the regular season starts. The early data from Baseball Savant tells a clear story: catchers have a slight edge, hitters are still adjusting, and everyone is still figuring out when to push the button.
Through the first weeks of spring action, teams have challenged 669 calls. They’ve won 345 of those challenges, good for a 52 percent overturn rate . That means when a player disagrees with the umpire badly enough to burn a challenge, he’s right about half the time.
The split between hitters and fielders is where it gets interesting.
Key Numbers:
Overall overturn rate: 52% (345 successful challenges out of 669 attempts)
Batters: 48% overturn rate (52 overturns, 108 attempts)
Fielders (catchers/pitchers): 55% overturn rate (100 overturns, 183 attempts)
ABS Challenge Success Rate (2026 Spring Training)
┌────────────────────────────────────────────┐
│ Overall ████████████░░░░░░ 52% │
│ Batters ██████████░░░░░░░░ 48% │
│ Fielders █████████████░░░░░ 55% │
└────────────────────────────────────────────┘Batters have challenged 108 calls and won 52 of them. That’s a 48 percent success rate, slightly below the overall average . There’s a theory floating around that shorter hitters might have an advantage because they know exactly where the top of their zone sits. The data isn’t there yet, but it’s worth watching.
Fielders, mostly catchers, have challenged 183 calls and won 100 of them. That’s 55 percent . Catchers stare at the zone for nine innings. They watch hundreds of pitches. It makes sense they’d develop a better feel for what should be a strike.
Some pitchers want nothing to do with the whole thing. Detroit Tigers ace Tarik Skubal said he probably won’t challenge calls unless it’s something egregious right down the middle. He’d rather leave it to his catchers. Braves lefty Chris Sale was even more direct: “I’m not an umpire,” he told reporters.
Spring training stats don’t matter. Everyone says that every year. But the way players use the challenge system, and how successful they are at using it, might actually carry over when the games count.
For now, the numbers say catchers have the edge. Hitters are catching up. And 52 percent of the time, the robot agrees with the player who complained.
Not bad for a first date.
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