MLB Introduces Automated Strike Zone in Triple A Pacific Coast League

The “robo-ump” debuted in the league for the first time this year.

Major League Baseball continues to experiment with potential rule changes in the minor leagues, and a big potential change has officially come to Triple A.

On Monday, a game between the Albuquerque Isotopes and the Salt Lake City Bees featured an automated balls and strikes system, also called the “robo-ump.” It was the first time the system was used in a Pacific Coast League game, having already come to the Arizona Fall League and International League.

Rockies outfielder Kris Bryant, who has been rehabbing with the Isotopes as he returns from injury, said he was encouraged by what he saw.

“I’m not totally against it,” he said, via Nick Groke of The Athletic. “Umpires want to get the calls right. They’re not out there trying to influence the game one way or the other. If they have a tool at their advantage to every call right, that’s great.”

One feature of the ABS is a bigger strike zone, since every pitch that clips the strike zone in any way is called a strike. Bryant acknowledged that he would like to see a little more unpredictability on borderline pitches.

“I wish there was more of, you have to have X percentage of the ball that crosses the zone for it to be a strike," he said. “Because the ones that just nick the corner, that's the gray area. As a pitcher you’re like, ‘maybe it's a strike?’ And as a hitter you're like, ‘I don't know either.’”

However, players were given tablets to see and understand why pitches were called strikes or balls to better understand how the system works.

Watch MLB games online all season long with fuboTV: Start with a 7-day free trial!

Besides the “robo-ump,” MLB has also implemented a pitch clock, limited pickoff attempts and an infield shift ban in select minor league levels.

• Daily Cover: A Search for Family, a Love for Horses and How It Led to Kentucky Derby Glory

Sports Illustrated may receive compensation for some links to products and services on this website.