The French defender has not featured for the Gunners since early October due to an Achilles injury but is in line to make his comeback in the group-stage clash at Emirates Stadium.
“He’s in the squad for tomorrow,” said Wenger of Koscielny. “It’s very good news because he was out for a while now and defensively we’re short in numbers. It’s good to have his quality back.”
Wenger, however, also confirmed that midfielder Jack Wilshere will be out “for a while” after suffering an ankle injury during Saturday’s 2-1 loss to Manchester United.
“I cannot give you any time-scale there,” said Wenger when asked about Wilshere.
“He will be out for a while. He has to see a specialist next week to see for how long he will be out. We don’t know at the moment.
“He has a big ankle sprain and I don’t want to talk about it because I’m not a medical specialist. The first news was that he will be out for the next few games.”
Wenger also delivered updates on Danny Welbeck, Theo Walcott and Wojciech Szczesny.
“Welbeck is in the squad, he had just treatment,” said Wenger. “I have not decided if he will start.
“Walcott is out with the groin problem he came back with from England. Szczesny is out.”
Wenger also confirmed that Olivier Giroud is unavailable for selection after he was not included in the squad for the Champions League group stage.
He added: “At the time when we brought Welbeck, we put him on the list. Giroud was supposed not to be available for the group stage. He’s back early which is good news but he’s not on the list for the 25 players selected.”
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