Catchers Win, Batters Guess: What a Full Season of Robot Umpire Challenges Showed

The first full season of baseball's automated ball-strike challenges is done, and the numbers say one thing clearly: if you're going to challenge, let the catcher do it.

There were 10,557 challenges, about 4.35 a game, and 5,686 of them, or 54%, overturned the umpire's call. Catchers were right 59% of the time. Batters were right 49% of the time. Pitchers, who rarely challenged, won just 40%.

Who used it best

Baseball Savant estimates the run value of every overturn. By that measure, the Reds gained the most, 16.8 runs, followed by the Angels (14.0), the Athletics (12.3) and the Twins (10.1). The Guardians were last at minus-13.4.

Being good at baseball didn't mean being good at challenges. The Dodgers (26th), Rays (25th), Cubs (21st), Brewers (20th), Braves (18th), Padres (17th), Yankees (16th) and Astros (15th) all finished in the bottom half.

The individual leaders

• Best hitters: Jose Altuve led with 5.6 projected runs gained, ahead of Cal Raleigh (4.6), Kyle Karros (4.5), Sal Stewart (4.4) and JJ Bleday (4.1).

• Best catchers: William Contreras saved 5.2 runs, just ahead of Patrick Bailey (5.1) and Francisco Alvarez (4.5).

• Costliest: Seiya Suzuki lost 5.7 runs on challenges, ahead of Shohei Ohtani (5.5), Ian Happ (5.2) and Michael Busch (5.1).

Three Cubs in the bottom four is a rough look for a team that just went out in two games.

Aaron Boone described it as "a new muscle for players to learn," an instinct to recognize in a second that a pitch was a ball and decide whether the situation is worth it. Houston's Joe Espada said it has made lineups more selective and forced pitchers to attack the zone more.

It's still in play this month. In the Padres' Wild Card clincher, 20-year-old catcher Ethan Salas won a first-inning challenge that turned a walk to Alex Bregman into a strikeout.