Arsenal manager Arsene Wenger expects England midfielder Jack Wilshere to miss the Gunners' Premier League match at home to Burnley on Saturday.
Wilshere is struggling with a knee injury that could also rule him out of Arsenal's Champions League match against Anderlecht next week.
But veteran French manager Wenger had better news on Friday regarding compatriot Olivier Giroud, whom he said was "miles ahead of schedule" in his recovery.
Arsenal and France striker Giroud fractured his foot against Everton in August but he is on course to rejoin training next month despite having initially been ruled out until the New Year.
"Olivier is miles ahead of schedule. He's doing very well," Wenger said Friday.
"He's three weeks ahead of schedule and he will join normal training after the international break. Of course it's a big boost."
Arsenal have seen Mathieu Debuchy, Abou Diaby, Yaya Sanogo, Laurent Koscielny, David Ospina, Mesut Ozil, and Giroud to injury this season and now Wilshere has joined that list.
However, Wenger -- whose side is currently fifth in the table, nine points behind leaders Chelsea, expects to have Wilshere back on duty against Swansea a week on Sunday.
"There is a slight problem with Wilshere. I don't think he'll be available against Burnley," Wenger said.
"It's very, very short term. He got a kick on his knee. I don't know if Anderlecht on Tuesday will be too early or not. He's not training at the moment. Certainly Swansea, yes."
- Walcott not ready -
Theo Walcott has been out since January with a major knee problem, but Wenger said Burnley was too soon for a first-team recall despite the England winger having recently played for Arsenal's reserves.
"Theo is not ready yet. He's been out for too long to start the game. If I can give him some competition I'm happy to do it," Wenger said.
"He's eager to play, but that is always the period when the patience of the player is tested.
"They feel ready and want to play. Usually they realise only much later they are not completely ready.
"I know Theo very well. He's an intelligent player so he knows as well that he's not completely there yet."
Victory over Burnley would give Arsenal a third straight win in all competitions and Wenger said the Premier League title was still in the Gunners' sights, although he accepted it would require a huge effort by his side to close the gap on London rivals Chelsea.
"I don't write us off, let other people do that, but Chelsea are in a strong position at the moment," Wenger said.
"I believe it would not be realistic to just think now that we'll catch Chelsea very quickly.
"We have to get consistent results to have a chance of coming back.
"I'm more focused on the quality of our games and on the consistency of our results before we think about coming back on Chelsea."
Bottom of the table Burnley have yet to win any of their nine league matches this season but have drawn four of those games and Wenger said Arsenal were prepared to be patient should Saturday's visitors to the Emirates Stadium adopt defensive tactics.
"It's absolutely normal that other teams try to stop us from playing our game. I can understand that completely," Wenger said.
"We want to be good enough to get around that and not allow other teams to stop us playing.
"We are good enough, but we know the quality of our passing and our decisions must be better."