Yet to invest any money during the summer and after a deflating opening day home defeat to Aston Villa, Arsenal travel to Turkey under severe pressure for the first leg of their Champions League playoff tie with Fenerbahce. As if Arsene Wenger’s problems weren’t already enough, he also heads to Istanbul with several injury concerns.

Thomas Vermaelen and Mikel Arteta were already ruled out for over a month leading into Saturday’s match, while a host of players suffered problems in the first competitive 90 minutes of the season to severely test a squad that has been trimmed during the summer. The most worrying injury was the one suffered to the knee of Alex Oxlade-Chamberlain. And there has been a strange conflict in prognosis from player and club

“He will be out for at least six weeks,” Wenger said in his pre-match press conference on Tuesday. “He has a posterior cruciate problem, a ligament which is stretched. We don't think it will need surgery. He is consulting tonight, but it will be at least six weeks out."

Later in the night, though, that story was contradicted by Oxlade-Chamberlain himself. “Gutted I'm injured so early in the season,” he tweeted. “But I'm going to be working hard to hopefully be back playing in three months. Thanks four all your support.”

Regardless of which diagnosis proves to be correct, the player is certainly unavailable for Wednesday night. There is, though, better news elsewhere. There had been concerns about a defensive crisis with full-backs Kieran Gibbs and Bacary Sagna also forced off against Villa with a cut to the head and neck injury, respectively.

“Everybody else should make it,” Wenger added. “There's a final decision [on Wednesday] but Sagna and Gibbs should be available.” The comments suggest Aaron Ramsey and Tomas Rosicky will recover from knocks, while Wenger also stated that Nacho Monreal, ruled out recently with a back injury, was available for selection.

With Laurent Koscielny’s suspension, as a result of his sending off against Villa, only applying to domestic matches, Wenger could elect to field an unchanged back four. Further forward, Santi Cazorla looks likely to come back into the side after starting on the bench at the weekend following his trip to Ecuador with Spain.

The big question for Wenger may be in the center of midfield. With Arteta out injured, Aaron Ramsey and Jack Wilshere were selected on Saturday and looked predictably lightweight and unable to prevent Villa from running in behind on numerous occasions to great cost. If Arsenal allow themselves to be that open at the Sukru Saracoglu then they could leave themselves in a real hole heading back to the Emirates the following week. However, Wenger’s failure to secure a much-needed defensive midfielder leaves him with little choice other than the inexperienced Emmanuel Frimpong.

Probable Lineups Fenerbahce

G: Demirel

D: Topuz, Yobo, Alves, Kadlec

M: Emre, Meireles, Potuk

F: Kuyt, Emenike, Sow

Arsenal (probable)

G: Szczesny

D: Sagna, Mertesacker, Koscielny, Gibbs

M: Ramsey, Wilshere

Walcott, Rosicky, Cazorla

F: Giroud

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