The Gunner Defender suffered a cut on his knee when he tried to prevent Alvaro Negredo from scoring City’s second goal.
“He has a cut and he will be out for a while, but for how long I don’t know,” Wenger said following the 6-3 loss.
Thomas Vermaelen is Arsenal’s only other recognised centre-back.
Wenger has also used full-back Bacary Sagna in central defence this campaign.
France international Koscielny, 28, and fellow central defender Per Mertesacker have been part of one of the tightest defences in the Premier League this season
Written by Steve Milne – Have your say below 🙂