Robots behind the plate? Why baseball’s challenge system is whole new ballgame for some umpires

Cincinnati Reds slugger Eugenio Suárez didn’t like what he saw when a pitch he was thrown in the sixth inning was called a strike in a game earlier this season.

So he challenged the call by home plate umpire C.B. Bucknor using the new Automated Ball-Strike (ABS) challenge system. The call, made during the March 28 game against the Boston Red Sox, was overturned and the called strike became a ball.

The same thing happened on the next pitch, as Suárez again challenged and again had a called third strike converted into a ball. He wasn’t the only player to successfully challenge two calls that game — his teammate Will Benson did, too.

This is the new world of Major League Baseball (MLB) where hitters, catchers and pitchers can challenge balls and strikes using the ABS challenge system that measures pitches against the strike zone for each batter in real time. In short, home plate umpires are having to adjust to the fact that a robot can check their work at any point in a game.

New challenge system, new rules

The ABS system calculates if a pitch falls within a two-dimensional strike zone that is calibrated to specified parameters for each batter — all the players were measured this year.

In each case, the strike zone is the full width of the plate, with the top of the strike zone set to 53.5 per cent of a given player’s height, and the bottom at 27 per cent.

And that’s what determines if the challenged call stands or not.

There are rules surrounding the challenges, including a requirement that they be made within two seconds of an umpire’s call.

Each team gets two challenges during regulation play. If the challenge is successful, they retain it. If it isn’t, they lose that challenge. So, if teams aren’t strategic about when they use the challenges, they could wind up with none left when they need them.

Called strikes and schadenfreude

Baseball umpires have long been the subject of ire, and that hasn’t changed even as the era of the robot ump has arrived.

In that March 28 game, for example, Bucknor saw six of eight challenges go against him — a detail recorded in the official boxscore.

The Red Sox, the team the Reds were playing, lost both their challenges early in the game. By the eighth inning, they were losing 5-4 and Trevor Story, Boston’s shortstop, tried to check his swing on an 0-2 pitch. Bucknor called it a strike and Story started arguing.

Boston manager Alex Cora came out of the dugout to pull Story away, but was then ejected by Bucknor himself.

The Reds went on to win, 6-5.

After the game, Cora spoke to the media about Bucknor.

“He has one job to do — call balls and strikes, and it wasn’t his best day,” he said.

“He’ll be the first one to accept it. I saw him putting his head down after one of the challenges … You know, it’s not easy, what we do and what he does.”

Bucknor has since faced a lot of criticism — including for another call he was involved in while umpiring at first base in a different game between the Milwaukee Brewers and the Tampa Bay Rays on March 31.

That call also got overturned via MLB’s replay review. Such replay challenges have used in baseball for years, but the ABS system at the plate is new to the majors this season.

Umpire Chad Whitson, meanwhile, saw seven of seven challenges go against him, in a March 28 game involving the New York Yankees and San Francisco Giants.

The Athletic pointed out that during the first weekend that the ABS system was in full use, Whitson was the only umpire graded worse than Bucknor in terms of overturned calls.

More recently, umpire Mike Estabrook saw six of seven calls at the plate overturned via ABS challenges in an April 3 game between the Arizona Diamondbacks and the Atlanta Braves.

And with some sports media outlets publishing running tallies of the success rate of the challenges, the potential seems high for continued schadenfreude over called strikes.

While the umpires behind home plate will undoubtedly see more challenges on some occasions than others, they can now be shown up by a robot over individual pitches.