MLB’s ABS System: A hit for fans, rough on umpires

SALT LAKE CITY – A week into the 2026 Major League Baseball season, and the automated ball-strike challenge system is outperforming any reasonable expectations.

The ability to challenge balls and strikes obviously injects strategy—but it turns out fans love playing along too.

A Game, a Season, a Heritage: Opening Day’s timeless magic

HISTORY IN NEW YORK 🗽

The first successful ABS challenge in MLB history 👏

pic.twitter.com/ROYDEsRII5

— BET99 Sportsbook (@BET99Sportsbook) March 26, 2026

Across the country, stadiums erupt with cheers—or jeers—as replays light up the big screen.

The system has been a raging success and, in most cases, has quietly reminded everyone how good MLB umpires usually are.

Of course, every system has exceptions—something veteran umpire CB Bucknor knows all too well.

ABSOLUTELY EMBARRASSING: Eugenio Suarez uses ABS on CB Bucknor on back-to-back pitches 😂 #Reds pic.twitter.com/K6wbsRGrAV

— js9innings (@js9inningsmedia) March 28, 2026

Bucknor has long been a punchline among players and fans for an egregious number of incorrect calls behind the plate. His 26 missed calls already highlight his struggles.

Suffice to say, ABS has been… less than forgiving to the 30-year veteran.

How does the ABS replay system work?

The ABS system, used at various minor league levels since 2022 and introduced in MLB Spring Training last year, allows pitchers, catchers, or batters to challenge a ball or strike call by tapping their head after a pitch—a signal for the umpire to initiate a review.

Challenges must be immediate and come without assistance from the dugout or other players.

Incorrectly Called Balls And Strikes
(MLB Umps In Their First Outing, via @UmpScorecards)

26 CB Bucknor
25
24
23
22
21
20
19 Chris Segal, Tripp Gibson, Lance Barksdale*
18 Ron Kulpa
17
16 Dan Iassogna, Ramon De Jesus
15
14 Ben May, Cory Blaser
13 Adrian Johnson, Bill Miller,… pic.twitter.com/J6gvWgOrIm

— Codify (@CodifyBaseball) March 31, 2026

Importantly, ABS does not replace the human element of an umpire calling balls and strikes behind the plate. ABS tracks every pitch in real time, but the data is only used for a challenge.

Each team begins the game with two challenges and loses one if the original call is confirmed correct. Teams retain challenges when correct.

When a pitch is challenged, an animated pitch graphic is shown on the in-stadium scoreboard and on the broadcast, giving fans a clear visual of whether the ball contacted the strike zone at the midpoint of home plate—the spot at which ABS evaluates every pitch’s location.

Follow Major League Baseball With KSL Sports

Find KSL Sports coverage of Locals in MLB here.

Take us with you wherever you go.

Download the new & improved KSL Sports app from Utah’s sports leader. You can stream live radio and video and stay updated on all your favorite teams.

Follow @bpreece24