Mohamed Elneny is expected to be out for three weeks after suffering ankle ligament damage during Arsenal's recent 2-0 win over Sutton United in the FA Cup fifth round.
The midfielder was replaced by Alex Oxlade-Chamberlain after the interval despite carrying on after picking up the knock midway through the first-half. He is believed to have undergone a scan during the week to gauge the extent of the injury.
According to Egyptian publication King Fut, the midfielder will not be able to train with the first team for at least three weeks, which will rule him out for key clashes against Bayern Munich in the Champions League, Liverpool in the league and the FA Cup quarter-finals against Lincoln City.
Arsenal are already light in midfield with injuries to Santi Cazorla, who is ruled out for the rest of the campaign, and Aaron Ramsey, who has been sidelined since the loss against Watford with a calf injury. Granit Xhaka and Francis Coquelin are the only two fit midfielders at the moment, but Oxlade-Chamberlain has put in strong performances to put himself into contention for a regular place.
Meanwhile, on a positive note, according to the London Evening Standard, Laurent Koscielny, who tweaked his hamstring during the recent 5-1 loss to Bayern in the first leg of the Champions League last-16 clash is expected to return to training this week. The French defender left the field after 49 minutes against the Bavarian giants after which Arsenal collapsed going from 1-1 to 5-1 in 40 second-half minutes.
Ramsey is also expected to return to training and is likely to be available for the clash against Liverpool, which will come as a major boost to Arsene Wenger, who has missed the added creativity from midfield in recent games. The manager admitted that it will be 21 days out for the Welshman after his latest injury, which should give him ample time to be fit for the game against the Reds at Anfield.