The 32-year-old was taken off minutes before the end, again with a calf injury and Munster head coach Tony McGahan was 'gutted' for Ireland hooker.
"It's certainly unfortunate if it is (a recurrence of the injury) because he has worked so hard to get back," Tony McGahan.
"He missed a significant part of last season and this was his first foray back into selection. So to be injured in the first 15 minutes of his comeback is devastating for him."
Munster return to Magners League action this weekend and welcome Italian side to Limerick on Friday evening.