Tommy Bowe has been ruled out of Ulster's crucial Heineken Cup tie at Leicester Tigers on Saturday.
The Ireland wing suffered a groin injury while on international duty in November but had hoped to make his return at Welford Road.
However, Ulster confirmed that the 29-year-old was ruled out following training on Monday.
A club statement read: "Bowe continues to recover well from the injury that he sustained playing for Ireland in November, however, it is not expected that he will be available for selection for Saturday's match."
Ulster also have doubts over Craig Gilroy after he suffered concussion and a broken nose during last weekend's win over Montpellier.
Tighthead Declan Fitzpatrick also suffered concussion and the pair must follow the strict return-to-play protocols.
"We'd be hopeful Craig will still be alright," said Ulster coach Mark Anscombe.
"He's taken a bit of concussion. It's just a slight knock. (The nose) is not too bad, a bit of a small break."
Unbeaten Ulster have already qualified for the Heineken Cup quarter-finals but they need to beat Leicester to ensure a home quarter-final.
Watch Leicester Tigers v Ulster live on Sky Sports 2 from 5.45pm on Saturday
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