Ireland captain, Paul O'Connell, and Conor Murray are both in a race to be fit for Munster's Heineken Cup quarter-final against Ulster.
The Munster teammates suffered knee injuries during Ireland's 17-17 draw with France in Paris and will miss the rest of the RBS 6 Nations fuelling doubts over their availability for the all-Irish Heineken Cup clash at Thomond Park on Sunday, 8 April.
O'Connell underwent a scan on his left knee after twisting it during the game and it has shown that he has picked up an injury to his medial collateral ligament. The two-time Heineken Cup winner's recovery period is likely to be between three and six weeks.
Scrum half Murray was replaced in the 59th minute of the game after falling awkwardly on his right knee. A scan has revealed bone bruising in the joint and while there has been no significant damage done to his ligaments, the injury does rule Murray out of the remainder of the championship with a expected three to four week recovery period.