On Aug. 26, 2017, Tom Koch-Weser sent an email to several colleagues in the Houston Astros front office that included an update on the state of the team’s “dark arts, sign-stealing department.”

Utility man Marwin González, Koch-Weser wrote, was having great success with the information procured by the Astros’ illicit efforts, cutting down on his rate of swinging at pitches out of the strike zone. But somebody else was having trouble with it: veteran outfielder Carlos Beltrán.

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