Arizona Diamondbacks manager Torey Lovullo talks to catcher Gabriel Moreno (14) during their game against the Seattle Mariners at Chase Field in Phoenix, on June 10, 2025. Joe Rondone/The Republic / USA TODAY NETWORK via Imagn Images

How the Diamondbacks Will Use New ABS Challenge System

Originally posted on Arizona Diamondbacks on SI
By Alex D'Agostino | Last updated Feb 13, 2026 8:00 AM ET

This upcoming season, MLB will implement the Automatic Balls and Strikes challenge system for the first time at the major league level. The Arizona Diamondbacks (and 29 other teams) are going to have to decide how to best utilize the new system.

The ABS challenge system was used at the minor league level in 2025, and was met with general positivity. Now, the big-leaguers will get a chance to try it out.

With that system comes a unique wrinkle to the game — one that will require strategic deployment. D-backs manager Torey Lovullo and GM Mike Hazen spoke about how Arizona will use the system at Cactus League Media Day on Thursday.

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What is the ABS Challenge System?

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The ABS challenge system is not a complete automatization of the strike zone. It is not a "robot umpire" system. Rather, teams will be given two challenges each game. Successful challenges will be retained, much like with in-play challenges. Only the pitcher, catcher or batter can challenge an umpire's call.

Per MLB.com, the ABS strike zone will be "a two-dimensional rectangle that is set in the middle of home plate with the edges of the zone set to the width of home plate (17 inches) and the top and bottom adjusted based on each individual player’s height (53.5% of the batter’s height at the top and 27% at the bottom)."

How Diamondbacks Will Use ABS Challenge System

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Lovullo said he's begun having conversations with the Player Development department about it, since that group has experienced it the most in the minor leagues.

"We started talking about that in a very general way," Lovullo said. "You want to have [a challenge] late in the game just in case, from what I've been told. ... At the top of the first inning on an 0-0 fastball, I don't want somebody to challenge and lose."

Lovullo said he's going to prioritize catchers having the opportunity to challenge over pitchers and hitters.

"Pitchers at times can get a little emotional. I know hitters sometimes are also going to be that way. ... From what I remember last year, and I can speak from that experience, the catchers were right the majority of the time. The hitters were about half the time. The pitchers about 10% of the time."

"But I want to be able to have one when I can, in pocket, in hand, when it's a very critical part of the game. And that might be in the fourth inning," Lovullo said.

Hazen said Arizona's strategy will not be "100% black and white."

"The organizational philosophy will marry with the coaching philosophy on what we ultimately decide from a team standpoint to execute with the players," Hazen said.

"We will have a strategy. ... There will probably be some things that we're focused on... based on the history of the ABS system in the minor leagues, and we'll see where it goes from there. I think it will be a learning process for everybody.I think the faster we learn how to execute on it, the better. But it will be something we work on in spring training," Hazen said.