Arsenal boss Arsene Wenger says defender Laurent Koscielny will miss Saturday's game against Hull City.
The Frenchman picked up the injury while on international duty with the French national team and joins Mathieu Debuchy on the sidelines.
"He [Laurent Koscielny] has an achilles problem, which has got worse," Wenger said during Thursday's press conference.
"He finds it difficult to play with it at the moment. You can only trust what the players says, he does not feel ready to play and will not play on Saturday.
"An inflammation of an achilles tendon, if you wait for it to be better, it can be a short time.
"If you want to get rid of it completely, it is long term. We will monitor him and as soon as he can take enough pain again he will play.
"No [surgery is required]. We have scanned him, there is no real deterioration of his achilles at all. It is just the pain of the inflammation."
Asked if midfielder Aaron Ramsey and striker Theo Walcott will feature against Steve Bruce's side, Wenger said: "Saturday's game is too soon for Aaron [Ramsey]. He will be back in full training on Monday and certainly in the squad for Wednesday [against Anderlecht].
"No, [Theo Walcott will not feature against Hull City].
"He will play tomorrow night in the under-21's. He has been out for nine months, Theo.
"He needs to find back some rhythm in the game and as well some confidence to go back into contact."
