Arsenal winger Alex Oxlade-Chamberlain will be out of action for longer than Arsene Wenger has predicted with the youngster admitting on Twitter that he is hopeful of returning after three months as he recovers from a knee injury.

Chamberlain picked up a knock during the Gunners' 3-1 defeat at the hands of Aston Villa at the weekend, leaving Wenger in a particularly difficult position as he suffers from a lack of depth in the squad already.

The manager confirmed that the England international won't feature in tonight's clash between Arsenal and Turkish side Fenerbahce, telling reporters: "He will be out for at least six weeks, he has a posterior cruciate problem, a ligament which is stretched.

"We don't think it will need surgery, he is consulting tonight (Tuesday), but it will be at least six weeks out."

But Chamberlain has admitted himself that the injury will likely keep him out for longer than this time frame, tweeting: "Gutted i'm injured so early in the season. But I'm going to be working hard to hopefully be back playing in 3 months. Thanks 4 all ur support. [sic]"

That would put Chamberlain in the frame to return to duty in November; after the end of England will have learnt their fate for the 2014 World Cup and Arsenal will be well and truly into the 2013/14 campaign.

The news has reportedly brought to Wenger's attention the need to purchase an attacking player before the end of the transfer window, though fans had been calling for the manager to act from the beginning of the summer to build on his forward line.

Wenger insisted to the press this week that the majority of transfer dealings would happen close to deadline day, arguing that he didn't have to justify his transfer policy to anyone.

"As always, we do what we think is right," he said. "When we think we have the right players, we do it.

"We were for years restricted and we competed with exceptional quality. This year we did not lose any players - we just lost two players with injury - but we will try to strengthen the squad and make the right decisions until the end.

"I repeat many, many times that the transfer window should be over before the season starts because it is a little bit destabilising once the season has started - to be there talking about what is not really important in football."