Mauer extended his hitting streak to 12 games with a two-run double down the left-field line in the fourth inning, but was noticeably limping as he ran into second base. Manager Ron Gardenhire and a team trainer came out, but Mauer remained in the game and was stranded.
The team said he has an oblique strain and will be evaluated Wednesday.
Left fielder Chris Parmelee moved to first base for the fifth inning.
Mauer is hitting .320 with 13 RBIs over his last 19 games.