Major League Baseball says it will investigate allegations the Boston Red Sox illegally used their video replay room to steal signs between opposing pitchers and catchers during their 2018 World Series championship season.

The claims were made Tuesday in a report by The Athletic. The website cited three anonymous sources it said were with the Red Sox during the 2018 season who said some players visited the replay room during regular-season games to get information on sign sequences.

The Red Sox say they will cooperate with MLB's investigation into the allegations.  

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