Mauer was scheduled to catch a bullpen before Thursday's game but didn't because the swelling in his quad hadn't gone down.
He took batting practice before the game and jogged around the bases but said his quad hadn't improve much from Wednesday. But he added that he hopes to return at some point this weekend against the Reds.
"I hope so," Mauer said. "It's not much better than yesterday. I thought I'd be able to do a little bit more. It's real frustrating."
Mauer, who is available to pinch-hit, is batting .314, with a .415 on-base percentage and .427 slugging percentage in 60 games.