Arsenal captain Mikel Arteta and defender Mathieu Debuchy are both set to be out of action for three months each, the English Premier League club announced Thursday as the injury crisis affecting the north London side intensified.
In a statement on their website, www.arsenal.com, the Gunners said Spanish midfielder Arteta's latest spell on the sidelines would be for "approximately three months" after the Spain midfielder underwent ankle surgery.
Arsenal said Arteta had had a bony spur that was causing him discomfort removed from his left ankle, adding: "The procedure went well and Mikel will now begin a period of rehabilitation which is expected to last approximately three months."
Arteta, 32, has not played for the London side since damaging a calf in the 2-0 Champions League win at home to Borussia Dortmund on November 26.
Arsenal manager Arsene Wenger said: "Mikel has had surgery which went well. I have just seen him, he is back with us at the training ground.
"He had a limited mobility in his ankle and some persistent inflammation that had an impact on his calf.
"That meant we had to make the decision to have surgery and it's a proper solution which gives him the best chance to recover," the Frenchman explained.
There was more bad news for Arsenal when Wenger said later Thursday that France full-back Debuchy, who suffered a dislocated shoulder following a shove by Marko Arnautovic in Sunday's 3-0 win against Stoke, was also facing three months on the sidelines.
"Mathieu had a surgery on his right shoulder following the injury on Sunday," said Wenger.
"It's very unfortunate for Mathieu, it's unbelievable because he's had two surgeries in the same season.
"He just came back, he played seven games and he's out again. I count three months out for Mathieu because contact will be a problem for the shoulder."
Debuchy has made only nine league starts since joining Arsenal from top-flight rivals Newcastle in pre-season and confirmation of the extent of his injury on Thursday means he is set for his second prolonged absence this term after three months out following ankle-ligament surgery in September.
Arsenal are also currently missing Jack Wilshere (ankle), Kieran Gibbs (ankle) and Abou Diaby (calf) all while Calum Chambers has been suffering with illness.
Danny Welbeck hasn't featured in Arsenal's last three matches because of a thigh problem and Wenger dashed hopes the England forward would return for Sunday's fixture away to Premier League champions Manchester City, although he was more upbeat regarding Gibbs.
"Kieran Gibbs will be training again with the squad on Friday and we will see how he goes from there. His news is positive," Wenger said.
"Danny Welbeck is not ready yet, he is still feeling some pain, so we will have to be patient."
Arsenal are presently fifth in the table, just a point off a Champions League place.
Last season's corresponding clash at Eastlands saw City thrash Arsenal 6-3.