MLB

2025 MLB Season Begins with a Historic First: The Era of the ‘Robot Ump’

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By
Colin Lynch
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Colin Lynch Sports Editor

Colin Lynch covers the NFL, MLB and WNBA for Heavy.com, with a focus on the New England Patriots. His sports coverage has been featured on The Sports Daily and Basketball Insiders, as well as FanSided's Chowder & Champions. A New Hampshire native and former D1 baseball player at St. John's University, Colin was drafted by the San Diego Padres in 2008 and enjoyed a four-year professional baseball career.

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Published28 Feb 2025

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2025 MLB Season Begins with a Historic First: The Era of the ‘Robot Ump’

Spring Training always brings a sense of renewal, a fresh start, a clean slate where every team, no matter how last season ended, can dream again. But when the defending champion Los Angeles Dodgers took the field against the Chicago Cubs on Thursday at Camelback Ranch in Glendale, Arizona, the story wasn’t about the players. It wasn’t about the final score—a lopsided 12-4 Cubs win—or even the return of baseball itself.

Instead, it was about the future of the game.

Because for the first time in Major League Baseball history, a game was played with a computerized ball-strike challenge system.

And just like that, the ‘robot ump’ era had officially arrived.

How the ABS Challenge System Works

The technology, known as the Automated Ball-Strike system (ABS), isn’t entirely replacing human umpires. At least, not yet. Instead, it allows pitchers, catchers, and batters to challenge a call at home plate, with the computer delivering a final, indisputable ruling in mere seconds.

It’s a system that has been years in the making.

Since 2019, MLB has tested ABS in various minor league levels, first using it to call every single pitch, then transitioning to a challenge-based format at Triple-A last season. In 2025, the system has been expanded to 13 Spring Training parks, ensuring every MLB team will play at least one game with the challenge system in place.

A Historic First Challenge

The first game featuring ABS didn’t take long to deliver its first historic challenge.

In the bottom of the first inning, with Cubs pitcher Cody Poteet on the mound against Dodgers slugger Max Muncy, an 0-1 fastball at 95 mph clipped the bottom of the strike zone. The home plate umpire called it a ball.

Poteet disagreed.

Without hesitation, the right-hander tapped his head, signaling the first official challenge in MLB history. In a matter of moments, the ABS system analyzed the pitch location, confirmed that it had in fact caught the bottom of the strike zone, and overturned the call.

Just like that, history had been made.

Smooth Sailing on Day One

For all the hype surrounding robot umps, Thursday’s game was remarkably uneventful on that front.

Only one other challenge was used the entire game, and the system worked without issue. Unlike other replay reviews that can slow down the game, ABS is immediate, displaying a visual representation of the pitch on stadium scoreboards within seconds.

“Everything worked well on Day One,” said MLB executive vice president Morgan Sword, who was on-site to monitor the debut. “A good first step.”

A Look at the Future: Will ABS Expand to the Regular Season?

For now, robot umps won’t be calling balls and strikes in regular season games. MLB officials remain in the evaluation phase, collecting data on how ABS performs in a controlled, Spring Training setting.

That being said, momentum is building.

In Triple-A games last season, the ABS challenge system did not significantly impact pace of play, with games averaging just 17 seconds longer than those without the technology. MLB’s key focus is ensuring accuracy without disrupting the flow of the game—something the league believes it can achieve with ABS in its current form.

Baseball’s Traditionalists vs. the Push for Accuracy

For baseball purists, the idea of replacing human umpires with technology has long been a controversial subject. The strike zone has always been subjective, shaped by the unique styles of umpires behind the plate. A call might be a strike one day, a ball the next—an inconsistency that has, paradoxically, become part of baseball’s identity.

But for many players and coaches, accuracy trumps tradition.

The introduction of instant replay for home runs in 2008 and expanded replay in 2014 were both met with skepticism, yet have now become essential parts of the game. Could ABS be next?

MLB commissioner Rob Manfred has made it clear that the league’s goal is to eliminate the most egregious missed calls, not strip umpires of their authority. But as technology advances and the demand for accuracy grows, the question may soon shift from “Will ABS be used in the regular season?” to “When?”