Arsenal manager Arsene Wenger fears he will have no option but to quickly buy a new centre-back should Sebastien Squillaci's hamstring problem prove a serious injury.
The Gunners face the prospect of taking on Ipswich in their Carling Cup semi-final first leg at Portman Road on Wednesday night with only two recognised central defenders after Squillaci picked up a muscle strain during Saturday's 1-1 FA Cup third-round draw against Leeds, when Arsenal needed a last-gasp penalty from captain Cesc Fabregas to keep them in the competition.
Given Thomas Vermaelen is still not yet match fit, Wenger accepts that should Squillaci face a lengthy lay-off, the squad would need immediate cover for Laurent Koscielny and Johan Djourou.
"If we only have two centre-backs then that cannot work with the number of centre-backs we have," said Wenger, who has been linked with a move for Bolton's Gary Cahill.
"If Squillaci has a problem then we must quickly go out for a player."
With two ties against the Tractor Boys, as well as battling for the Barclays Premier League and the toughest of European assignments Barcelona, Wenger will not have wanted to add another fixture into their congested schedule.
However, after again not making the most of first-half chances, notably through Andrey Arshavin, who failed to convert when clean in on goal after 11 minutes, the final outcome against Leeds could have been much worse.
Arshavin, and also Nicklas Bendtner, found themselves jeered by some sections of the home crowd after time and again promising moves broke down.
Wenger, though, has every confidence Arshavin will soon display the top-class football he is capable of on a regular basis.
"The fans were frustrated. That comes from when you don't win," the Arsenal manager said.
"The fans are demanding. We were not consistent technically and so they picked on our inconsistencies. "It is not through a lack of desire with Arshavin. He wants to do well.
"He took one touch too many with his first chance and the keeper did well to save another shot he had.
"Every player during a season has strong and weaker periods and he has had a weaker period, then two or three weeks on the bench."
Wenger continued: "I have no worries that Arshavin will come back into the team, but their confidence does suffer a little bit from that.
"We try to analyse our games in an objective way and I am lucky because our players are self critical, they analyse themselves well and they want to do well."