The England midfielder sustained the problem late on in the first half of the Champions League clash at Emirates Stadium and Wenger revealed that he is now set for a spell on the sidelines.
Speaking at his pre-match news conference at Arsenal’s London Colney training base on Friday morning, Wenger said: “We lost Oxlade-Chamberlain and it is quite serious. It will keep him out for a few weeks.”
The Arsenal boss also revealed that he would make a late decision about whether to include defender Gabriel Paulista in Sunday’s squad after his lay-off with a hamstring problem.
He continued: “Gabriel has a test, we will see about him tomorrow. We still need to be cautious with Danny Welbeck.”
Arsenal head into Sunday’s clash looking to build on their 2-1 victory over Leicester in the Premier League in their most recent outing.
The north London side are currently third in the table and two points off top spot heading into the final 12 games of the campaign.
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