PAUL O'CONNELL and Keith Earls are in a race against time to be fit for Munster's Heineken Cup semi-final against Biarritz after both Ireland stars were left out of the squad for Saturday's Magners League clash against the Ospreys in Thomond Park.
Both players are suffering from groin injuries and, while team manager Shaun Payne said he was "confident" they would be available, he admitted their lack of preparation would have to be factored in.
"We need them training. They can't go into a game with any preparation at all," said Payne. "It's an injury that needs rest and the more you load it the worse it's going to get.
"We'd be confident that both of them will be available, but these are difficult injuries and they are very frustrating for us to have to deal with. There is obviously a situation where there will be a cut-off point."
O'Connell has not played since Ireland's loss to Scotland which would mean if he starts against Biarritz it would be more than five weeks since his last match.
Winger Doug Howlett and Ian Dowling are nursing hamstring and knee injuries respectively but are expected back next week while prop Tony Buckley is in the squad but carrying a knee injury.
Brian O'Driscoll starts for Leinster tonight in a top versus bottom Magners League clash against Connacht at the Sportsground (7.45). Connacht are desperate to get something as they chase Ulster, who are four points ahead with a game more played.
Meanwhile, scrum-half Peter Stringer is set to stay with Munster despite overtures from Ulster who are looking for a replacement for Leinster-bound Isaac Boss.
Having failed to land Scotland captain Mike Blair, Ulster were pursuing South African Ruan Pienaar having already captured his Sharks team-mate Johann Muller, and Ulster sources confirmed that the 91-times capped Stringer was also "definitely in the mix".
However, Stringer, who has been with the province since 1998, is expected to complete a new deal with Munster while Pienaar's father this week rubbished reports that his son -- who can play scrum-half, out-half or full-back -- would be moving to Ulster.
"I know nothing about that," said Gysie Pienaar. "I wouldn't know why they would be saying that. Ruan's Sharks contract runs until the end of next year and he wouldn't want to leave now. Maybe after the World Cup."
With Boss joining Eoin Reddan at Leinster and Tomas O'Leary first-choice at Munster, if Stringer stays it will mean Ireland's four top scrum-halves are at two provinces.