Midfielder Aaron Ramsey could return to action for first time in over a month for Arsenal's must-win Champions League match against Dinamo Zagreb.

The 24-year-old, out since 20 October because of a hamstring injury, took part in training on Monday.

Midfielder Francis Coquelin is out for two months, while Theo Walcott and Alex Oxlade-Chamberlain are not match fit.

Zagreb will be without midfielder Arijan Ademi who was given a four-year ban by Uefa after failing a drugs test.

"Certainly for the next two months we play without Coquelin," said Gunners manager Arsene Wenger.

The Frenchman will also be without midfielder Mikel Arteta who, like Coquelin, suffered an injury in the 2-1 defeat at West Brom, as well as Jack Wilshere, Danny Welbeck and Tomas Rosicky who remain sidelined.

"We've been hit very hard in November because until the Sheffield Wednesday game in the League Cup we had a good record. But since we have lost a few players," added Wenger.

Arsenal, who lost 2-1 to Zagreb in the opening match of the Champions League campaign in September, need to win and hope Olympiakos lose to Bayern Munich to have any chance of overhauling them for second place in the group.