Brandon Belt holds the record for the highest number of pitches in one at-bat in MLB history, having worked a 21-pitch at-bat on April 22, 2018, against Jaime Barria of the Los Angeles Angels. Belt hit 16 foul balls before eventually hitting a fly ball to right field, and the at-bat lasted for 13 minutes. This is the longest at-bat on record since 1988, as far back as data is available. Below are some other notable at-bats with high pitch counts:

• Ricky Gutierrez, SS, HOU vs. Bartolo Colon, RHP, CLE June 26, 1998: 20 pitches, flyout
• Yadier Molina, C, STL vs. Matt Garza, RHP, MIL September 25, 2012: 20 pitches, single
• Kevin Bass, RF, HOU vs. Steve Bedrosian, RHP, PHI July 23, 1988: 19 pitches, flyout
• Alex Cora, 2B, LAD vs. Matt Clement, RHP, CHC May 12, 2004: 18 pitches, home run

It is worth noting that Belts record has been surpassed in a Spring Training game by the Mets Luis Guillorme, who worked a 22-pitch walk on March 14, 2021, against Cardinals right-hander Jordan Hicks.