England winger Walcott returned from a side strain, while Bendtner is fit following a car crash earlier in the week. manager Arsene Wenger revealed that he took a gamble bringing on Eduardo against Olympiakos.
"It was a gamble to play him and unfortunately his muscle injury got worse," the Frenchman said. "He will be out. It is the same thigh muscle and has recurred a few times now. But Walcott and Bendtner are available.''
Walcott is raring to get back into action and insists his belief in ending the club's trophy drought led him to signing a new contract.
The England striker agreed new terms towards the end of last season and is determined to win his first silverware since arriving from Southampton in 2006, the season after Arsenal lifted their last cup.
"I signed because I have got a lot of belief in the club and in the team," Walcott said. "We have gained a lot of experience over the last few years and although we haven't won any trophies, I think that will change this year.
"If you want to win trophies, it is important to keep the group together - Manchester United are a good example of that.
"This summer, Robin (Van Persie), Nicklas, Kieran [Gibbs] and a few others signed new contracts and I firmly believe we can win things here. We've also added to the squad with Thomas Vermaelen and for me he is a top lad - he's our top scorer too.
"He has settled in really well and he's such a nice guy. I have trained with him a few times now and he's a very tough competitor. He has got an absolutely great leap on him too - he will win a header against anyone. I reckon he would beat Peter Crouch in the air.''