Wales hooker Richard Hibbard looks to have played his last game for the Ospreys after undergoing shoulder surgery.
It means the hooker, who is moving to Gloucester, is likely to have played his final game for the region.
Hibbard featured in all of Wales' matches during the Six Nations, starting the first four before being used as a substitute against Scotland.
"Richard has an ongoing shoulder problem that has been troubling him, and after returning to the region this week he feels unable to continue playing," said the Ospreys medical performance manager, Chris Towers.
"It is in his best interests to get this issue resolved and he will undergo surgery today.
"The expected minimum recovery time for such a procedure means it is unlikely he will play again between now and the end of the season."