​Major League Baseball has fined the Arizona Diamondbacks and pitching coach Ariel Prieto each an undisclosed amount after Prieto wore a smartwatch in the team's dugout Wednesday night.

Smartwatches and other digital devices have been banned by MLB since the Boston Red Sox were found to be using an Apple Watch to steal signs during a game earlier this season.

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According to a statement from the league, investigators found no evidence Prieto used his Apple Watch "for any purpose in the dugout, nor any baseball-related communication," during the game.

The statement acknowledged that Prieto violated league rules by having the device and said the fines would be donated to hurricane relief efforts in Puerto Rico.