Liverpool's Michael Owen has been ruled out for three weeks after scans revealed he tore a thigh muscle in the Uefa Cup win against Steua Bucharest.
Boss Gerard Houliier had hoped Owen would be fit to face Birmingham on Sunday, despite limping off late in Thursday's 1-0 win at Anfield.
But Houllier revealed an examination had discovered "torn muscle
fibres" in his right leg.
Owen now faces a spell on the sidelines after the latest injury blow in a frustrating season.
Houllier said: "It is not just a strain and the scan proved something was wrong. He will need to rest for the first few days then proper treatment.
"Once he is recovered we will have to build the muscle up through rehabilitation. It is nothing to do with any previous problems he has had. It was purely an accident when he played the ball."
Owen damaged his shin during the 2-1 home defeat by Arsenal on 7 October and was ruled out for England in Turkey and the next two Liverpool matches.
He has also suffered ankle problems and has played only three of the last nine Liverpool matches - and it may be Christmas before the striker is back in action.
Harry Kewell's goal gave Liverpool a 2-1 aggregate win against the Romanians and a place in the competition's third round, but the gloss on the victory was taken off by Owen's substitution two minutes from time.
Houllier said he was impressed by his team's desire to replicate their 2001 Uefa Cup triumph.
Houllier said: "There was a sense of desire about my team, they wanted to
stay in Europe and continue the experience. I cannot fault their willingness and
"It was tense at the end. In the last 15 minutes you are not going to score
again so we needed to do a professional job with discipline and playing safe.
"It was important that we will still be in Europe in February when
the Champions League teams come into the competition.
"It will give the lads confidence and experience. The game was a difficult
one to approach. Do you go for the throat and take risks or do you defend and
keep a clean sheet?
"We kept our discipline and picked them off with Harry's goal. Do not forget
we had a young team out there, they maybe lacked experience of these sort of games.
"But we have done the job, we are in the draw for the next round and we know
we have beaten a very good team.
"They were very difficult to break down and had some excellent players."