MLB's top prospects deal with good, bad of 'robot' umpires

SCOTTSDALE, Ariz. (AP) — First baseman Ali Sanchez was standing in the on-deck circle so he had a great vantage point of the two-strike breaking ball to Jacob Heyward. It finished so low that by the time it reached the catcher it nearly bounced in the dirt.

Sanchez — like everybody else who was watching this game on a Tuesday night in the Arizona Fall League — had an immediate mental reaction.

"That's a ball," Sanchez said.

Not so fast in the brave new world of "robot" umpires.

Heyward, a San Francisco Giants prospect, was rung up for strike three and then thrown out of the game by human home plate umpire Jose Navas following a brief disagreement with the call.

Heyward's frustration was understandable considering the location of the pitch. The problem was this: Navas was just the messenger.

The Arizona Fall League is the latest professional baseball league to experiment with a computer that judges balls and strikes. The TrackMan system makes its nearly instantaneous decision and sends a signal to the human home plate umpire, who then makes the call.

After about 25 games of the TrackMan at Salt River Fields, there's something of a consensus: The system has its quirks and problems — particularly on breaking balls low in the zone like the one that frustrated Heyward — but it also has promise.

"It's definitely unique, it's different from everything we've learned throughout our baseball careers," Arizona Diamondbacks prospect Seth Beer said. "It's just something new. Something that guys are just a little uncomfortable with so far."

Beer, Sanchez and pitchers Jackson Rees and Tristan Beck all agreed the TrackMan system is excellent on the inside and outside corners but struggles when judging breaking balls low or high in the zone.

"The really loopy breaking balls...

source https://www.chron.com/sports/article/MLB-s-top-prospects-deal-with-good-bad-of-14560149.php