Mayer is absent from Wednesday's lineup versus the Rays due to back and neck stiffness, Ian Browne of MLB.com reports.
Red Sox interim manager Chad Tracy is hopeful that Mayer will be available to pinch hit. However, with a team off day looming Thursday, the club could elect to stay away from Mayer on Wednesday with the goal of having him return to the lineup Friday, when the Red Sox begin a three-game set against the Rangers.