Arsenal manager Arsene Wenger has confirmed that Laurent Koscielny will miss Sunday's North London derby against Tottenham Hotspur through injury.
The defender is struggling with an ankle problem which ruled him out of Wednesday's Champions League win against Olympiakos.
"Koscielny looks to be definitely out for Sunday," Wenger told reporters. "It looks short for him. He couldn't absorb any test today."
The Frenchman also revealed that forward duo Theo Walcott and Gervinho are both doubts for the match, although Walcott is the more likely to feature.
"For Walcott and Gervinho a decision will be made on Saturday or Sunday," he added. "The most likely to be fit of the two looks to be Walcott."
The Gunners are currently 13th in the Premier League, while Spurs occupy sixth place.