Ospreys have suffered a double injury blow with lock Lloyd Ashley ruled out for the rest of the season and wing Hanno Dirksen also on the sidelines.
Ashley, 24, suffered a knee ligament injury in their European Champions Cup exit at Exeter last weekend.
Dirksen went down with an ankle ligament problem in the same game.
Ashley will have surgery and will not be available again during the 2015-16 season while Dirksen is not expected back until mid-March, 2016.
Former Wales Under-20 lock Ashley has often captained Ospreys in the absence of Wales second-row Alun Wyn Jones this season.
His injury ends any hopes Ashley had of forcing his way into Wales contention this season.