MESA, Ariz. — As Major League Baseball prepares to implement the Automated Ball-Strike (ABS) system during the 2025 regular season, the Chicago Cubs are still adapting to the technology. Right-hander Gavin Hollowell, who played for Triple-A Iowa, experimented cautiously with the ABS last season, initially leaving decisions about challenges to his catchers before attempting one himself late in the year when he thought a called ball might have been a strike.
And I was wrong, so I won’t be challenging anymore,
Hollowell told the Tribune with a laugh.
Though MLB used the ABS system in Triple-A since 2023 and during the 2025 spring training games, most Cubs players have limited exposure, mainly due to the technology’s availability only in certain ballparks equipped with Hawk-Eye and Statcast data. This restricted practice primarily to select road games, as venues like Sloan Park, the Cubs’ spring training facility, lacked the necessary data capture capabilities.
Limited Prior Usage Among Cubs Players
Several Cubs players, including left fielder Ian Happ, had little or no opportunity to use the system in exhibition games last spring. Their limited encounters with ABS during spring training stemmed from the team’s schedule, which included an unusual number of home games and a trip to Japan for the Tokyo Series, limiting their chances to try the system firsthand.
I’ve never seen it in action,
Happ said.
It’s going to be important throughout spring to get a look at it and challenge. You’ve got to see what it feels like, you’ve got to get your bearings on your eyes. … It’s a new system for all of us. I think the league will adapt, similar to pitch clock and everything. It’ll be a quick transition.
Preparing the Team for In-Game Challenges
The Cubs plan to dedicate time during spring training to develop strategies on when and how to best utilize ABS challenges. Manager Craig Counsell indicated that a structured meeting is expected at the end of spring training to establish clear guidelines for challenge usage, addressing practical concerns such as timing and consistency in umpires’ responses.
Counsell voiced apprehension about potential disputes over challenge calls and timing:
Players are going to get this wrong, and we’re going to get: Why didn’t we challenge?
He added,
There’s going to be some of that. Maybe we’ll find out it’s pretty hard to be an umpire — I think that’s probably what we’ll find out.
Rules and Restrictions of the 2025 ABS System
The ABS system introduces several new rules intended to maintain fairness and keep the game flow efficient. A challenge can only be initiated by the pitcher, hitter, or catcher using a double tap on the head within two seconds of the umpire’s call. Umpires may deny challenges if they suspect outside influence on the call. Each team receives two challenges for a nine-inning game, retaining a challenge if a call is successfully overturned. Additional challenges are granted during extra innings if previously unused.
Umpires have discretion to adjust baserunner placements if a challenge affects the course of a play. The system prohibits challenges when a position player pitches. Importantly, any part of the baseball crossing the strike zone results in a strike, with the strike zone dimensions customized to each hitter’s height following pre-season measurements.
Measures to Prevent Misuse and Maintain Integrity
MLB has introduced safeguards to prevent cheating with the ABS technology. Pitch location data will be delayed by approximately five seconds when accessed via official channels, and teams are barred from operating their own pitch tracking systems in ballparks, limiting data access exclusively to MLB’s Hawk-Eye technology. Furthermore, MLB will review all challenges to ensure integrity and detect any irregularities.
Statistical Trends from Testing Periods
During the 2024 Triple-A season, games averaged roughly 4.2 ABS challenges with a 50% overturn rate, a figure consistent with the 4.1 challenges per game and 52% overturn success observed in 2025 spring training. The strike zone under ABS maintains a fixed width of 17 inches, with the vertical extent tailored individually based on verified player measurements conducted during spring training.
Pitching Perspectives on ABS Adjustments
Cubs pitching coach Tommy Hottovy noted pitchers might benefit from the ABS’s more clearly defined strike zone, particularly in corner areas that could now consistently be called strikes.
That’s something we might try to play around with and see if we can take advantage of more of those type of pitches,
he said.
You have an understanding of how you think it’s going to work, but a lot of it’s just read, react. How did that work? What can we do differently? And make those adjustments.
Training and Adaptation Approaches During Spring
To help players adjust, the Cubs have incorporated practice sessions focused on the ABS strike zone, using pitching machines that simulate different edge pitches. Catcher Carson Kelly explained that they have practiced making simulated challenges to refine their judgment of the zone’s boundaries.
It’s an exciting addition to the game, but also it can come down to being very important,
Kelly remarked.
I think it’s going to be very apparent when those big moments are happening and there’s a big pitch that needs to be made, if they execute or if it’s just off, it’s worth the challenge.
Live Testing and Player Reactions
Recently, during batting practice at Sloan Park, the Cubs ran live ABS challenges with unlimited attempts per at-bat, aiming to boost comfort with the system before the regular season limits each team to a set number of challenges. For example, catcher Miguel Amaya challenged a pitch from Colin Rea that was called a ball; the ABS review confirmed the pitch was just outside the strike zone by 0.3 inches.
Hollowell, reflecting on the ABS system, acknowledged a blend of traditional and modern perspectives.
I like the old school, let the umpire do his job kind of thing, but it’s exact,
he said.
It sometimes feels like you’re throwing into a shoebox, feels a little small, but we know it’s probably accurate. I enjoy it from the accuracy standpoint.
Implications for the Cubs and MLB Ahead
The rollout of the ABS presents a significant shift in game dynamics, demanding both players and officials adapt to new procedures and technologies. For the Chicago Cubs, early engagement with the system during spring training and batting practice is vital to minimize in-game confusion and optimize challenge strategies. How effectively the Cubs and their players absorb and deploy the ABS may impact their game management and outcomes in the 2025 season, while also contributing to MLB’s broader effort to modernize officiating standards.
