Wales centre Cory Allen looked set to be ruled out of the remainder of the RBS 6 Nations after suffering an ankle injury on Saturday.
Allen was carried off on a stretcher early in the second half of Cardiff Blues' defeat to Leinster at Arms Park.
The injury, should it prove as serious as it appeared, will further limit Warren Gatland's midfield options and comes as another blow to the four-cap centre who was ruled out of the World Cup after one game.
There was further concern for Gatland after Bath's defeat to Wasps as fly-half Rhys Priestland suffered a knock at the Recreation Ground.
"Rhys has got a sore dead leg, but he has said he is fine," Bath head coach Mike Ford said. "It is not too bad."
Uncapped England back Ollie Devoto also went off at half-time.
"Ollie took a knock - I am not too sure if it is concussion," Bath head coach Mike Ford said, who described the centre as feeling "groggy".