So far in the 2026 MLB season, CB Bucknor has been the most challenged umpire, leading the list with six challenges, all in a single game where the Cincinnati Reds defeated the Boston Red Sox. The veteran umpire had to endure each of those overturned calls.
“He had six — six! — calls overturned via the ABS challenge system, including back-to-back pitches by Eugenio Suarez in the sixth inning. There were eight challenges in the game overall, five by the Reds (5 for 5) and three by the Red Sox (1 for 3),” wrote Mike Axisa on March 28 for CBS.
Other umpires have also been heavily tested by the ABS challenge system early in the season. Doug Eddings and Laz Diaz each have five challenges so far, with three overturned calls apiece.
The most challenged umpires early in 2026
Some umpires have clearly felt the pressure when players challenge calls. It often shows on the home plate umpire’s face when they have to activate the microphone and announce that a batter or catcher has challenged a pitch, with even pitchers occasionally getting involved.
Umpire CB Bucknor (Michael Reaves/Getty Images)
| Umpire | Challenges | Overturned calls |
| CB Bucknor | 6 | 6 |
| Doug Eddings | 5 | 3 |
| Laz Diaz | 5 | 3 |
| Will Little | 4 | 0 |
| Lance Barrett | 4 | 3 |
With only a handful of games played, this season could turn into a record-setting year for challenges, especially for veteran umpires who have long been scrutinized for controversial calls.
While pitcher-initiated challenges are still relatively rare, they have appeared early in 2026, even though managers like Alex Cora made it clear before the season that they prefer pitchers not to use the ABS system.
Could challenges become “unlimited”?
Each team is allowed two challenges on balls and strikes. If the umpire’s call is overturned, the team keeps the challenge; if the call stands, they lose one. Given the pace seen on Opening Day, where some games featured multiple successful challenges, it’s fair to expect home plate umpires to face a high volume of reviews throughout the season, adding another layer of pressure to their role.
The first challenge of the 2026 season
José Caballero initiates the first ABS Challenge, Powered by T-Mobile.
— MLB (@MLB) March 26, 2026
The call was upheld as a strike.
(MLB x @TMobile) pic.twitter.com/7w4SZB95mn
The first challenge of the season came from Jose Caballero of the New York Yankees, who disputed a strike call by Bill Miller against the San Francisco Giants, though the call was not overturned. The first successful challenge belonged to Francisco Alvarez on March 26, one day after the first ever challenge. This time, the call was reversed, overturning a ball call in his favor.
