Arsenal right-back Mathieu Debuchy will miss the next three months after undergoing ankle ligament surgery, manager Arsene Wenger has confirmed.
Debuchy damaged the area in the 2-2 draw with Manchester City, missing subsequent games against Borussia Dortmund and Aston Villa, and could be out for the remainder of the year with the injury.
The 29 year old had played every minute in the Premier League this season before limping off against City and his absence will be a major blow to an Arsenal team who have made an uncertain start to the campaign.
"He has had surgery and will be out for three months," Wenger told Arsenal.com. "A reasonable delay is three months.
"It all went well, but it can be a week or two earlier or a week or two later, but it will be around three months.
"It is a blow of course, how big it will be we will only know afterwards because it will be down to how well we replace him. We bought [Calum] Chambers for that."
Elsewhere Arsenal are set to welcome back a host of players after the upcoming international break, Wenger has confirmed.
Theo Walcott hasn't played since January due to a knee injury but is closing in on reaching full fitness, while Serge Gnabry and Yaya Sanogo are on the verge of recovering from respective knee and hamstring problems.
The trio are therefore all in contention to face Hull City on 18 October before the resumption of Arsenal's Champions League campaign against Anderlecht, with Nacho Monreal also in contention to feature after an improvement to his back problem.
Wenger said: "He [Monreal] is not far, but he is not ready yet. [Sanogo] is similar, he will be back after the international break.
"Theo is doing very well, and Gnabry is doing very well too. They should be available after the international break for full training."