Triple-A Worcester will place Mayer (hip) on the 7-day injured list Tuesday, Alex Speier of The Boston Globe reports.
Mayer first suffered a hip/glute injury in late July while playing at Double-A Portland, and despite getting promoted to Worcester more than a week ago, he has yet to be cleared for his Triple-A debut. Before getting the call to Worcester, Mayer slashed .307/.370/.480 with eight home runs and 13 steals in 77 games at Portland.