C.B. Bucknor’s worst overturned calls: Tracking every bad decision from MLB’s most controversial umpire

Some of MLB's most controversial umpires, including Angel Hernandez and Joe West, are now retired, but one often-criticized umpire has hit a new low in the era of the automatic ball-strike (ABS) system.

C.B. Bucknor has already found himself in the middle of multiple controversies in 2026, from bizarre calls behind the plate to an errant call at first base.

Controversy isn't new for Bucknor, who has been involved in his share of on-field disputes in his long career as an umpire, but fans are beginning to wonder whether he is qualified at all to still be making calls on a daily basis.

Here's a look at the worst moments for Bucknor in 2026.

MORE: Explaining MLB's new ABS challenge system

C.B. Bucknor overturned calls tracker

March 28: Red Sox vs. Reds

Bucknor was one of the earliest targets of fans' ire under the new ABS system, as he saw six of his ball-strike calls overturned in a March 28 game between the Red Sox and Reds. Several other pitches that were called strikes appeared to be outside the zone, Umpire Scorecards found. 

Despite the new technology fixing many of Bucknor's mistakes, Red Sox manager Alex Cora saw enough and was ejected when Trevor Story erupted following what he believed was a check swing.

After the game, Cora told reporters, "He has one job to do. It wasn't his best day."

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March 31: Rays vs. Brewers

Bucknor was caught up in a controversy of his own making on March 31, when he inexplicably called Milwaukee's Jake Bauers out for supposedly not touching first base.

Bauers had no trouble reaching base after Rays 2B Ben Williamson had trouble handling a line drive and made a poor throw to try to recover, but Bucknor ruled that Bauers was tagged out after not stepping on first base. Replay showed that Bauers stepped on the base as any player would normally do, and it wasn't even clear whether Bucknor was looking in his direction when he made contact with the base.

CB Bucknor strikes again, this time saying the runner did not touch first base. He very clearly did pic.twitter.com/zn6k9RtLXl

The call was quickly overturned, but Bucknor's initial assessment of the situation was mystifying to fans in Milwaukee and fans at home. 

MORE: Full details on C.B. Bucknor's bizarre out call

C.B. Bucknor ABS challenges

March 28: 6 overturned calls

Bucknor's first game behind the plate this season saw eight challenges and six overturned calls. His accuracy was 88 percent, 5.5 percent below the expected mark according to Umpire Scorecards, and a couple of called strikes that were overturned to balls weren't particularly close to the zone:

How long has C.B. Bucknor been in MLB?

Bucknor has been umpiring professionally since 1996, as he served as a National League umpire from 1996-99 before handling both leagues from 2000 onward. Bucknor has umpired well over 3,000 games in his three-decade career.

C.B. Bucknor age

Bucknor is 63 years old; he is set to turn 64 in August.

Through the first 35 games of the 2026 season, the 10 oldest umpires had an overturn rate of 69 percent on ABS challenges, compared to 39 percent for the 10 youngest, according to Codify Baseball.