ABS All-Stars: MLB's Best Challengers at Each Position

It's All-Star season in baseball, as the fan vote for the American and National League All-Star teams is underway. And given that the 2026 MLB season is the first year the ABS challenge system is being utilized at the big-league level, we thought it was only fitting that the best of the best at challenging balls and strikes got some recognition.

Note: Minimum five challenges for hitters, minimum 10 challenges for catchers, no minimum for pitchers

C: Carson Kelly, Cubs

Chicago Cubs catcher Carson Kelly (15) receives a new ball from the umpire — Carson Kelly has built considerable trust with the Cubs pitching staff when it comes to challenging balls and strikes. | Charles LeClaire-Imagn Images

Few catchers have been as impactful as Kelly with the ABS challenge system. Kelly’s 78% success rate (on 37 challenges) ranks fourth among catchers who have made at least 10 challenges, and he has gained the third-most strikeouts and eliminated the fourth-most walks for the Cubs pitching staff. Most impressive of all? The majority of Kelly’s challenges have come in the later innings of games, and he has created 1.5 net runs as a result of his challenges, the best mark in baseball.

1B: Sal Stewart, Reds

Sal Stewart, Cincinnati Reds, ABS challenge — Reds first baseman Sal Stewart has won more challenges than any hitter in baseball. | Aaron Doster-Imagn Images

Not only is Stewart in the running for the National League Rookie of the Year award thanks to his stellar production at the dish, but he’s also been baseball’s best hitter at utilizing the ABS challenge system. No hitter has been more aggressive with the new implementation than Stewart, who has challenged more pitches (30)—and had more successful challenges (20)—than any hitter in the game. Stewart’s excellent eye for the strike zone and experience with the ABS system in the minor leagues has served him well on many challenges, like this one to flip a strikeout.

2B: Jose Altuve, Astros

Jose Altuve, Houston Astros, ABS challenge system — The Astros have been one of the best teams at utilizing the ABS challenge system and Jose Altuve is one of the biggest reasons why. | Denny Medley-Imagn Images

Altuve, possessing one of MLB’s most compact strike zones, was expected to benefit from baseball’s new ball-and-strike arbiter. And he has, as the Astros second baseman has won the second-most challenges (12) of any hitter while flipping four strikeouts. Altuve is a big reason why Houston has been one of the best clubs in the business at utilizing the ABS challenge system.

3B: Isaac Paredes, Astros

Isaac Paredes, Houston Astros, ABS challenge system — Isaac Paredes has yet to lose a challenge this season. | Troy Taormina-Imagn Images

Paredes, along with another ABS All-Star, is one of just three players who has challenged a minimum of five pitches to boast a perfect success rate. The Astros third baseman has flipped two strikeouts and a walk, leads hitters in net runs created off challenges and may boast the most impressive challenge of any player this season.

SS: CJ Abrams, Nationals

CJ Abrams, Washington Nationals, ABS challenge system — Nationals shortstop CJ Abrams is a perfect 8-for-8 on ABS challenges this year. | Rafael Suanes-Imagn Images

Boasting a perfect 8-for-8 challenge record, Abrams is both an ABS All-Star and a likely National League All-Star. The Nationals shortstop leads hitters in ABS overturns more than expected and ranks second in net runs created, meaning he doesn’t just boast a perfect challenge record—Abrams’s challenges have been incredibly impactful to Washington’s success.

OF: Davis Schneider, Blue Jays

Davis Schneider, Toronto Blue Jays, ABS challenge system — Blue Jays left fielder Davis Schneider is a proven veteran of the ABS challenge system. | William Liang-Imagn Images

If there was an ABS All-Star team in the minors, Schneider would have been on it last year. Before getting the call up to Toronto, Schneider led all Triple A batters who had challenged at least 10 pitches with an 83% success rate. And the ABS wizard has continued to show his wisdom for the Blue Jays in 2026, as Schneider has won 77% of his 13 challenges, the best mark among outfielders.

OF: Bryan Reynolds, Pirates

Bryan Reynolds, Pittsburgh Pirates, ABS challenge system — Pirates outfielder Bryan Reynolds has flipped the most strikeouts and walks among hitters using the ABS challenge system. | Sergio Estrada-Imagn Images

Reynolds leads all hitters in ABS challenges that have eliminated strikeouts and gained walks while winning the sixth-most challenges among position players. Not only has Reynolds been aggressive with the new system, he’s been impactful.

OF: Teoscar Hernández, Dodgers

Teoscar Hernandez, Los Angeles Dodgers, ABS challenge system — Dodgers outfielder Teoscar Hernandez's veteran eye at the plate has served him well when challenging balls and strikes. | Denis Poroy-Imagn Images

Along with Mookie Betts, Hernández is among the Dodgers’ better hitters at utilizing the ABS challenge system. The veteran slugger has tapped his helmet 10 times and has been correct on seven of those challenges, including one flipped strikeout.

DH: Kyle Schwarber, Phillies

Kyle Schwarber, Philadelphia Phillies, ABS challenge system — Phillies designated hitter Kyle Schwarber is among the leading hitters in successful ABS challenges. | Kyle Ross-Imagn Images

Schwarber doesn’t just lead MLB in home runs—he’s also adept at challenging balls and strikes, as the Phillies slugger has won the fifth-most challenges at a strong 64% clip. So confident is Schwarber in his knowledge of the strike zone that in one instance he began walking up the first-base line after challenging a 3–0 pitch before the results of the challenge were even shown.

SP: Freddy Peralta, Mets

Freddy Peralta, New York Mets, ABS challenge system — No pitcher has won more ABS challenges than the Mets' Freddy Peralta. | Sam Navarro-Imagn Images

While this season hasn’t quite gone the way Peralta or the Mets envisioned when they dealt for him this winter, the veteran righthander can say that he’s been the best starting pitcher at utilizing the ABS challenge system. And while that’s unfortunately not saying much—the pitcher success rate on challenges this season is 35%—Peralta is still the only pitcher to make three successful challenges thus far.

RP: Ryan Helsley, Orioles

Ryan Helsley, Baltimore Orioles, ABS challenge system — Orioles pitcher Ryan Helsley has only challenged one pitch this season but he made it count. | Jay Biggerstaff-Imagn Images

Helsley has only challenged one pitch so far this season, but it was quite a consequential one. Clinging to a two-run lead in the top of the ninth vs. the Twins on March 29, Helsley challenged a 3–2 pitch to Josh Bell and successfully flipped a walk to a strikeout for the second out of the inning. Oh, and Helsley’s hat tap also resulted in the first ABS-induced ejection, as Twins manager Derek Shelton argued that the Orioles closer hadn’t challenged quickly enough to no avail.

Honorable mentions

C: J.T. Realmuto, Phillies
1B: Nick Kurtz, Athletics
2B: JJ Wetherholt, Cardinals
3B: Kevin McGonigle, Tigers
SS: Xander Bogaerts, Padres
OF: Corbin Carroll, Diamondbacks
OF: Taylor Ward, Orioles
OF: Aaron Judge, Yankees
DH: Bryce Eldridge, Giants
SP: Chris Bassitt, Orioles
RP: Blas Castaño, Rockies

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