Arsenal captain Cesc Fabregas has been ruled out of the trip to Manchester United in the FA Cup after failing to recover from the injury that forced him to limp off against Barcelona on Tuesday night, with goalkeeper Wojciech Szczesny also unavailable.
Arsene Wenger confirmed the Spanish midfielder, who admitted to playing through pain at Camp Nou before eventually being substituted, will not play any part at Old Trafford and could miss Arsenal's next league match at West Brom.
He told reporters: "He had a recurrence of his hamstring problem and he will be out for the next game, maybe for the next two games.
"He is, of course, very disappointed because it is becoming a little problem for him to keep having a recurrence of his hamstring [injury], but it's a very superficial one."
Polish stopper Szczesny, who withdrew early on in Arsenal's defeat to the Spanish giants, is also out of the quarter-final tie against Sir Alex Ferguson's side, with Wenger confirming the 20-year-old "is out for a while" and will have to see a specialist to determine the extent of his finger injury sustained by collecting a powerfully struck shot from Barcelona full-back Dani Alves.
"Szczesny has a dislocated finger with a tendon problem,” said Wenger. “We need the assessment of the specialist to see where we go from here.
"He had a scan last night. He is out for a while, for how long? I couldn’t tell you.”
Manuel Almunia will more than likely start in the FA Cup after shining as a substitute at Camp Nou, while young stopper James Shea should be on the bench, and Wenger could yet ask the Premier League to allow him to bring in an emergency loan to cover the goalkeeping slots.
Asked whether he was considering making a temporary signing, Wenger indicated that he was but had not asked for permission from the league just yet and refused to state who it was he was interested in but did confirm that it would be a signing that would provide cover beyond this weekend's game.
Meanwhile, the absence of Fabregas in midfield is compounded by Alex Song's unavailability. The Cameroonian sat out last week's draw with Sunderland and the Barcelona game, with Abou Diaby, Denilson, Tomas Rosicky and Aaron Ramsey all in contention to start at Old Trafford.
There is good news for the Gunners, however, as striker Robin van Persie is fit to face Manchester United. The Dutchman was a surprise starter at Barcelona after making a faster than expected recovery from injury, but was controversially sent off for two bookable offences.