Arsenal manager Arsene Wenger has confirmed William Gallas will be sidelined the rest of the season with the knee injury he sustained in Tuesday's 1-1 Champions League draw at Villarreal.
The Gunners defender damaged the medial ligament in his right knee during a collision with striker Giuseppe Rossi at El Madrigal.
Wenger feared after the match that Gallas had suffered a serious injury and a subsequent scan confirmed the French defender will be out of action for several weeks.
Full-back Gael Clichy will miss two weeks with a back injury, while Robin van Persie and Eduardo will undergo fitness tests on Friday before Saturday's Premier League match at Wigan Athletic.
Wenger said: "It is not the best news for Gallas. He's a quick recoverer but we think it will be too short to come back before the end of the season. It is a big blow but the squad comes in.
"We are on a strong run in the league and want to keep the run going. We did that even without the injured players. We have improved as a team and shown mental strength.
"We want just to focus on the short term and not look back too much.''
Wenger will hope for better news tomorrow when striker Robin van Persie and Croatia forward Eduardo undergo fitness tests which could see them return for Saturday's Premier League game at Wigan.
Long-term absentee Tomas Rosicky is "not close'' to playing again, according to Wenger.
Wenger, however, believes it is important Arsenal, currently lying fourth six points behind Chelsea, try to clinch third spot in the league.
"It is super important to keep the run going,'' said Wenger. "Consistency is the real sign that we have improved and at the moment we are quite consistent.
"It is important that the team gives a good collective performance. We are a team which relies on our passing and the quality of our collective play.
"We lost three players on Tuesday night so we have to rely again on our depth in the squad which is quite strong. Until now we have dealt well with our problems.''
Wenger warned against complacency in the Champions League following his side's encouraging away performance against Villarreal and believes only Barcelona, who beat Bayern Munich 4-0 at home in their first leg, have clinched a semi-final spot.
The Arsenal boss also said no-one should write off Liverpool, even though they were defeated 3-1 at Anfield by Chelsea.
Wenger said: "Arsenal v Villarreal and Manchester United v Porto are still to be decided. Barcelona looks to be through completely and Chelsea are in a strong position.
"But it is still to be decided because Liverpool can respond and be strong away from home. Everywhere you play at the moment you have to be completely 100%. If you are just a little bit off your best you get punished.''