Ulster are likely to be without their Ireland squad members for Friday's Magners League clash with Edinburgh at Murrayfield.
Skipper Rory Best, Paddy Wallace, Tom Court, Andrew Trimble and Stephen Ferris could be earmarked to come under the Ireland player management programme ahead of next month's four-game autumn series.
It would be a big blow to Ulster in the wake of Sunday's Heineken Cup thumping in Biarritz, which saw their unbeaten record shattered.
Coach Brian McLaughlin would love to have a full squad available for the visit to Edinburgh, although Scotland's Simon Danielli is certain to miss out with a shoulder injury.
"We have to respond quickly and positively to last week's defeat," said McLaughlin. "We had our chances in Biarritz in the first half and had high hopes. But they stepped up a couple of gears and we just could not handle it.
"We have got away with it in the Magners League, but Biarritz are a completely different kettle of fish."
Meanwhile, forwards Robbie Diack and Declan Fitzpatrick have signed new three-year extended contracts, while centre Darren Cave has committed himself to Ravenhill until June 2013.
One of five South Africans in the Ulster squad, Diack will find himself eligible to play for Ireland come July, having been resident in the country for the requisite three-year period.
Cave, who was capped twice for Ireland the summer before last, has been a regular at outside-centre this season.
Fitzpatrick (28), sidelined with a calf injury, was originally brought over to Ulster from London Irish by Allan Clarke in 2001, but it is only the past couple of seasons that he has flourished as a tight-head.
He has won a couple of Ireland A caps and proved a useful replacement for BJ Botha when the Springbok was away on Tri Nations duty at the start of this season.