Paul O'Connell is unlikely to play for Munster again this season as a result of the ankle injury picked up during the province's win over Leinster at Thomond Park on Saturday night.
O'Connell was withdrawn six minutes into the second half against Leinster, after landing badly from a line-out.
The captain has not suffered a break, but doctors have to wait for bad swelling to reduce before a final examination is possible.
It appears likely that O'Connell has either snapped his Achilles tendon or damaged his ankle ligaments. The Munster captain will travel to Dublin on Monday for further medical examination.
Munster will face Brive away in the quarter-finals of the Amlin Challenge Cup next Saturday afternoon, a game O’Connell is sure to miss. Mick O’Driscoll is likely to deputise in the second row.