Robo umps are coming to major league spring training, but they won’t make it to the field yet.

The automated balls-and-strikes software, alternatively called “ABS” or “ESZ” (electronic strike zone), will run in the background during exhibition games for testing and development purposes, according to Major League Baseball and umpiring officials.

The technologically enabled balls-and-strikes system involves an umpire wearing an earpiece while in his normal stance behind the catcher. The software tracks the flight of the ball and declares to the umpire “ball” or “strike,” and the official announces the call.

MLB Commissioner Rob Manfred told Fox Business on Wednesday that the league would implement the automated system in spring training games in the 2020 season, which would mark a major acceleration in the timeline of bringing an electronic strike zone to big league action, even if only in exhibition games.

“We’re going to be using it during spring training and in some of our minor leagues this year,” he said. “The way it works is the camera calls the ball or strike [and] communicates to an earpiece that the umpire has in his ear. And from the fan’s perspective, it looks exactly like it looks today. We believe, over the long haul, it’s going to be more accurate. It will reduce controversy in the game and be good for the game. We think — we think it’s more accurate than a human being standing there.”

Players, coaches and fans have clamored for such reform after a heavily scrutinized postseason of umpiring that saw decisions on balls and strikes often called into question.

But fully instituting ABS immediately in spring training would have run afoul of the new collective bargaining agreement between MLB and umpires that was brokered around Christmastime. The five-year agreement included provisions for increased umpire compensation and retirement benefits designed to let older officials retire sooner in exchange for umpires’ cooperation in implementing the new strike zone technology.

“To achieve this new contract with the owners, however, we agreed that MLB can use ESZ technology, if important conditions are met, and after a process through which umpires will have direct input into when and how the technology enters Major League games, including spring training games,” the Major League Baseball Umpires Association said in a statement. “We believe our involvement will be crucial to preserving fair play if the owners are determined to introduce this fundamental change.

“We bargained hard for these protections, and the process we negotiated has not even started. Use of ESZ technology in spring training games this year would be premature and would violate our new agreement."

A person with knowledge of the system’s rollout said Manfred is eyeing activating the digital strike zone in the big leagues in as soon as three seasons.

Even after umpires and franchise owners reached their new agreement, tensions remain high between the two groups. Umpires have protested the way Manfred has pushed for what they consider the rapid implementation of technology into officiating the game, and the way the commissioner has treated players who have had on-field run-ins with officials.

The new labor deal sought to cool those tensions and allowed MLB to experiment with ABS in the minor leagues, Arizona Fall League and the independent Atlantic League, the laboratory where the system was first used in 2019.

An MLB spokesman said Thursday that officials plan to use ABS in live action again in the Arizona Fall League and Atlantic League in 2020, along with the Class A Advanced Florida State League. Nine of the 12 ballclubs there play in major league spring training ballparks that are already equipped with the hardware necessary for the electronic strike zone.

A Florida State League official, though, said MLB had not finalized the details with teams over the use of the technology. The last update the farm league received was that developers were focused on cutting down the lag time between when a pitch crosses home plate and when the umpire is alerted whether the offering was a ball or strike.

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