Left-back Bacary Sagna withdrew through illness on the eve of this week's Champions League clash against Villarreal, while Gibbs picked up a groin problem late in the victory.

Gunners boss Arsene Wenger is already without Gael Clichy (back), William Gallas (knee) and Johan Djourou (knee) for Wembley.

"We still have Sagna as a doubt for the weekend," said Wenger. "And after Villarreal we have Kieran Gibbs as doubt too. He has a little groin problem. Clichy, Almunia and Djourou are still out."

Goalkeeper Manuel Almunia will also miss the semi-final with his ankle injury, meaning Lukasz Fabianski will deputise, but who plays at left-back instead of Clichy and Gibbs is less straightforward.

"There is the option to play Sagna in there if he has recovered," Wenger said on Arsenal TV Online. "The other is to play (Mikael) Silvestre there and put (Alex) Song at the back.

"There are not many options but we'll deal with the situation no matter what happens.

"I am happy to take 48 hours more so I can assess the [injury] situation. Also it means I can look back at how I rotated before and, as well, how we can keep the balance right considering the opponent.

"We have to rotate a little bit because we play every three days now and only the squad can achieve what we want to achieve."

Almunia and Djourou are a fortnight away from action, while Clichy needs two-and-a-half weeks of rest. It means they are all doubts for the first leg of the Champions League semi-final against Manchester United.

The good news for Wenger is Andrey Arshavin and Eduardo are both available for Wembley.