From Jay Jaffe:
While Beltrán was not mentioned by name in Rosenthal and Drelich’s January 7 report of the Red Sox’s own sign-stealing efforts, last week I noted that it was possible to connect the dots between him and the timeline laid out by The Athletic’s intrepid pair. “As far back as 2015, the Yankees used the video replay room to learn other teams’ sign sequences, multiple sources told The Athletic. Other teams likely were doing the same. Sources said the Red Sox began doing it no later than 2016.” Beltrán played for the Yankees from 2014-16 before being traded to the Rangers on August 1 of the latter year; he signed with the Astros in December 2016.
Such circumstantial evidence hardly proves Beltrán’s involvement in New York, but as noted within that article, player movement from team to team appears to have played a significant role in the proliferation of electronic sign-stealing efforts throughout the game. “Oftentimes it takes a player to show up and be like ‘You f—— morons, you’re not doing this?’” one American League executive told The Athletic.
(Needless to say, reports of the Yankees’ 2015 participation should also serve as a reminder that the apparent guilt of the Astros and Red Sox may be the tip of the iceberg in this mess, a point that The Athletic has frequently underscored but that appeared to escape Manfred back in November when he said he had “no reason to believe it extends beyond the Astros at this point in time.”)