MLB has implemented the Automated Ball-Strike (ABS) Challenge System for the 2026 season. It allows players to challenge a ball or strike call made by the home plate umpire.
As of the trade deadline on August 3, over 7,100 challenges have been issued across MLB, with a 53% success rate — essentially a coin flip — but slightly in the challenger's favor. Teams are averaging just over four challenges per game.
Who’s best at challenging calls? The edge definitely belongs to catchers more than halfway through the 2026 regular season:
- Catchers: 59% success rate (3,707 attempts)
- Hitters: 48% success rate (3,294 attempts)
- Pitchers: 36% (122 attempts)
Here are the team and individual leaders, through August 3, per MLB.com.
MLB Team Rankings Based on the Best ABS Overturn Percentage
- 63% – Reds
- 62% – Diamondbacks
- 59% – Tigers
- 58% – Rangers
- 57% – Athletics, Cubs, Royals, Dodgers
- 56% – Marlins
- 55% – Phillies, Twins, Rockies
- 54% – Astros
- 53% – MLB average: Yankees, Red Sox, Cardinals, Angels
- 52% – Blue Jays, Mets, Rays, Nationals
- 51% – Braves, Mariners, Orioles, Padres
- 50% – Brewers, Giants
- 46% – White Sox
- 45% – Guardians
- 43% – Pirates
Batters With the Best/Worst ABS Overturn Percentage
Troy Taormina-Imagn Images
Best batter percentages (min. 10 challenges):
- 85% – Isaac Paredes, Astros
- 82% – Nick Kurtz, Athletics; CJ Abrams, Nationals
- 79% – Davis Schneider, Blue Jays; Bryce Eldridge, Giants
- 73% – Esmerlyn Valdez, Pirates
- 70% – Brent Rooker, Athletics
Worst batter percentages:
- 26% – Josh Naylor, Mariners
- 27% – Junior Caminero, Rays; Willi Castro, Rockies; Ceddanne Rafaela, Red Sox; Oswald Peraza, Angels; Spencer Horwitz, Pirates
- 29% – Jonathan Aranda, Rays
Pitchers With the Best/Worst ABS Overturn Percentage
Cary Edmondson-Imagn Images
Best pitcher percentages (min. 2 challenges):
- 100% – Chris Bassitt, Orioles
- 75% – Kyle Freeland, Rockies
- 67% – Drew Anderson, Tigers; Max Fried, Yankees; Walker Buehler, Padres
- 50% – Freddy Peralta, Rays; Hogan Harris, Athletics; Michael Lorenzen, Rockies; Jesus Luzardo, Phillies; Joey Cantillo, Guardians
Worst pitcher percentages:
- 0% – Cristopher Sanchez, Phillies; Gregory Soto, Pirates; Yennier Cano, Orioles; Osvaldo Bido, White Sox; Sean Burke, White Sox
- 25% – Shane Baz, Orioles
- 33% – George Kirby, Mariners; Bubba Chandler, Pirates; Calvin Faucher, Marlins
Catchers With the Best/Worst ABS Overturn Percentage
Brad Penner-Imagn Images
Best catcher percentages (min. 20 challenges):
- 80% – J.T. Realmuto, Phillies
- 76% - Sandy Leon, Braves
- 74% - Mitch Garver, Mariners
- 72% – Tyler Stephenson, Reds
- 71% - Salvador Perez, Royals; Agustin Ramirez, Marlins; Carson Kelly, Cubs
- 70% - Kyle Higashioka, Rangers
Worst catcher percentages:
- 32% - Jhonny Pereda, Mariners
- 42% - Drew Romo, White Sox
- 43% - Brandon Valenzuela, Blue Jays; Samuel Basallo, Orioles; Drew Millas, Nationals
How the ABS Challenge System Works: The Basics
- Each team receives two challenges to start the game.
- Only batters, pitchers, and catchers can challenge a call.
- If a team wins a challenge, it can keep challenging. If a team challenges incorrectly twice, it loses its challenges for the rest of the game.
- Teams will start each extra inning with a challenge regardless of whether they have already exhausted their challenges in the first nine innings.
