As baseball leans further into analytics, MLB has decided there’s one line teams shouldn’t cross. With the second half of the season about to begin, the league has cracked down on the use of generative AI for live in-game decision-making, removing teams’ access to the custom tab on its league-issued dugout iPads.

The move prompted one executive, quoted by The Athletic’s Eno Sarris, to remark, “Gotta stop the cheating before there’s cheating now.”

Rather than simply serving as a source of preloaded scouting information, some teams were reportedly using custom apps on the league-issued dugout iPads to access generative AI that could recommend substitutions, pitch calling, and other in-game decisions traditionally made by players and coaches. According to The Athletic, people familiar with the technology estimated that as many as one-third of MLB teams used the dugout iPads for at least one of these purposes.

These dugout iPads were first introduced in 2016 to help managers and coaches track data through built-in apps that were under the league’s supervision. In 2021, they added a new feature that allowed players to watch live in-game video from the dugout. However, the footage could be viewed only after a one-inning delay.

The same year, MLB also introduced stricter rules around the dugout iPads after the sign-stealing scandal. Players and coaches were also prohibited from using them to browse the internet or social media, with close monitoring ensuring that such issues didn’t come up. At the time, former MLB executive Chris Marinak said the league-issued iPads were “completely locked down and monitored,” allowing players to access only MLB-approved applications.

Since then, teams have urged MLB to slightly relax the rules. They now have custom tabs that allow teams to put their own preferred data. Ultimately, these custom tabs turned out to be problematic.

“MLB is banning the custom tab on the dugout iPads due to as many as ten power-user teams pushing the envelope on what is considered live inputs. Apps were generating pitch and substitution suggestions,” The Athletic’s Sarris wrote on X.

According to The Athletic, MLB has three tabs on its dugout iPads. One tab contains all the Statcast data and advanced metrics of the players. The second one contains information related to the newly introduced ABS, and the third one is the custom tab. It includes information unique to each team, like player tendencies, matchup information, defensive positioning, and other scouting material that teams previously used pen and paper for. Teams will still be allowed to upload static information that is available before first pitch, but anything added to the custom tab will remain subject to MLB review.

The commissioner’s office issued the memo on June 11, giving teams more than a month to adjust before the policy took effect on Wednesday, just ahead of the start of the second half.

Pitch-calling from the dugouts is reportedly one of the major issues MLB aims to tackle with this move. Jack Lambert, director of baseball operations at Driveline Baseball, also holds the same opinion.

“With someone live-scoring the game, teams could chart pitch type and location to get dynamically updating game plans,” Lambert remarked. “Those plans could determine if their approach at the plate should change as they face the lineup a second (or) third time in the game, and could also be applied to live pitch-calling.”

The Athletic also reported that some clubs were feeding ongoing game information into their AI models to anticipate the next pitch or recommend what should be thrown, although it remains unclear exactly how many teams used the iPads with live in-game information.

The recent ban, however, did not bring any punishment for the teams, as all were reportedly found compliant with the league’s rules governing sign stealing and electronic-device usage. Still, the midseason policy change has reportedly frustrated some front-office members focused on innovation. “It’s caused quite the stir,” one high-ranking research and development official told The Athletic, even as MLB moved to curb the growing use of AI-assisted in-game strategy.