Mayer was removed from Wednesday's game against the Phillies due to right wrist discomfort, Chris Cotillo of MassLive.com reports.
Mayer went 0-for-1 with a walk and a run scored before his wrist forced him out of the game in the fifth inning. The severity of his injury is unclear, but a day off for the Red Sox on Thursday will give him extra time to recover and possibly allow him to be ready for Friday's series opener against the Dodgers.