Gavin Thornbury will see a surgeon today over a knee tendon injury suffered last weekend and, along with skipper Paul Boyle, will be out for some time for Connacht.
Second row Thornbury made his Ireland A debut against the All Blacks XV last month.
But the 29-year-old now faces another lengthy spell on the sidelines having previously had to deal with a serious shoulder injury.
READ MORE: All guns blazing v Munster for Ross Molony and Leinster as lock hits milestone
Thornbury picked up the knee injury in Saturday's Challenge Cup victory in Brive. Back row stalwart Boyle sustained a shoulder injury in the same game.
"We’ll cross the bridge of their expected return when it happens," said Connacht head coach Pete Wilkins, who wouldn't put a timeframe on their possible return.
"It’s bad timing and horrific luck for the two of them.
"Particularly Gav who has had a fair number of injury lay-offs in recent seasons, we want to make sure he is alright and there is support behind him.
"I don’t know the details but there is a tendon injury in there which makes it pretty significant.
"He’s seeing a surgeon today so after that we will know more then, it will certainly be a number of weeks if not more. We’ll wait and see but it is serious."
Former Connacht player Tietie Tuimauga escaped without a card when he and fellow Brive prop Daniel Brennan caught Boyle high.
Ex-Connacht No 8 Abraham Papali’I was sent off for a no-arms tackle on Shamus Hurley-Langton.
Asked if there was anger in the westerners' camp over what occurred, Wilkins said: "There are always emotions running high at the time.
"For us, we’re more concerned about the boys and once we get an update on the seriousness of the injuries and the length of the lay-offs, that is the main thing.
"Away games in France are very emotional and competitive and physical. There are always aspects that will catch the eye.
"There were a few former Connacht players out there and it was hard to diagnose if there was intent or not.
"Certainly there was no ill-feeling between the players and afterwards and now we’ll just gather around the players who got hurt and support them through the rehab."
Connacht are enjoying an upturn in fortunes and resume their URC challenge on Friday with a home tie against Ulster, who are looking for a first win in four games.
"We love the intensity of the matches when we play them, whether that’s here or at Belfast or Dublin even," said Wilkins.
"We really relish these encounters and it’s something that makes for a really special week in terms of our preparation.
"And then you add in the disappointment of how we performed up there right at the start of the season. There are lots of aspects of that performance we’ve improved upon since then.
"But also we need to close the emotional loop on that and make sure we deliver this weekend. So there are bags of incentives for us this week."
READ NEXT:
Irish relative of World Cup winning hero Alexis Mac Allister hoping he brings trophy to Ireland
Roy Keane leaves Gary Neville and Ian Wright in fits of laughter with comments after World Cup final
League of Ireland newcomers Kerry FC appoint Billy Dennehy as manager
Ballyhale answer all the questions to reach another All-Ireland club final
Get the latest sports headlines straight to your inbox by signing up for free email alerts
