Wales captain Dewi Lake is a major injury doubt for Ospreys’ United Rugby Championship derby against Scarlets in Swansea on Saturday.
The hooker, 25, suffered a bicep injury in training and Ospreys are waiting on the results of scans.
Wales will also be nervous about the outcome, with their Six Nations opener against France in Paris on 31 January.
“We are just checking on Dewi,” said Ospreys head coach Mark Jones.
“He took an accidental bump in training to his bicep.
“We’re just assessing what that looks like at the moment, in terms of what part of the bicep and what needs to be done, if anything, to get him in a position to play.
“We’re going to leave that one as long as we can because he’s an important player and we’d love to have him around. I’m waiting to hear back myself on some clarity.”