Ireland head coach Andy Farrell has been handed another injury concern after Jack Conan suffered a shoulder injury during Leinster's Champions Cup victory over Clermont Auvergne.
The 34-year-old back-row was forced off shortly after scoring a second-half try in Saturday's 48-23 victory in France.
Leinster boss Leo Cullen has confirmed Conan faces a spell on the sidelines, although the full extent of the injury remains unclear.
The setback comes at a difficult time for Ireland, with captain Caelan Doris already set to miss November's Nations Championship fixtures.
Leo Cullen delivers worrying Jack Conan update
Conan played his part in Leinster's impressive victory before his afternoon ended early.
Speaking after the match, Cullen admitted the injury did not look promising.
"He will be out for a little bit with that, I'd say. We'll get the exact extent of that in the next week," Cullen said.
The injury leaves Conan in doubt for Leinster's United Rugby Championship clash with Munster at the Aviva Stadium on Saturday, October 24.
Further medical checks will determine how long the Ireland international faces on the sidelines.
Andy Farrell faces double injury blow
The timing could hardly be worse for Ireland.
Farrell is already preparing for November without captain Caelan Doris, whose recovery from knee surgery has been delayed by an infection.
Now Conan, another experienced option at number eight, faces an uncertain period on the sidelines.
Losing both players would leave Farrell with a significant selection headache ahead of the Nations Championship.
However, Conan has not yet been officially ruled out of Ireland's November fixtures.
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Positive news for Jamison Gibson-Park
There was at least some encouraging news for Leinster and Ireland.
Cullen confirmed scrum-half Jamison Gibson-Park came through his latest training week without any major problems.
The Ireland star could now return against Munster next weekend.
His potential comeback would provide a welcome boost for Leinster, with Farrell also hoping to have the experienced number nine available for international duty.
