The Tigers placed Flaherty on the 15-day injured list Saturday with a left peroneal strain.
Flaherty was forced to end his start Friday against Cleveland prematurely due to injury, and further evaluation determined he'll need to spend time on the IL due to complications with his outer ankle. Hao-Yu Lee was recalled from Triple-A Toledo in a corresponding move, though Casey Mize (thigh) is expected to return from the injured list Sunday and will presumably act as Flaherty's replacement in the rotation.