London: Arsenal will be without defender Laurent Koscielny and forwards Theo Walcott and Gervinho for Wednesday`s Champions league match against Olympiakos, manager Arsene Wenger said on Tuesday.
Koscielny has an ankle injury, Walcott a knee problem and Gervinho a mild muscle strain although all three could be fit for Sunday`s Premier League match against Tottenham Hotspur.
Arsenal drew their opening Champions League Group F match against Borussia Dortmund 1-1 and lie 13th in the Premier League after a disappointing start to the season.
The north London club`s problems have been compounded by the loss of England midfielder Jack Wilshire, who will be sidelined for between four to five months after surgery to repair a stress fracture to his right ankle.
Wilshire has not played a competitive match this season after sustaining the injury in a pre-season friendly against the New York Bulls at the Emirates stadium.
Wenger bolstered his midfield during the off-season, bringing in Mikel Arteta and Yossi Benayoun to add experience.
"(Wilshere`s injury) makes us a bit shorter in midfield and it puts a bit more pressure on our midfielders to perform game-in, game-out, because we will have less rotation possibilities," he was quoted as saying on the Arsenal website (www.arsenal.com).
"But every club can be tested on that front so it shouldn`t impact our end result of the season and shouldn`t be any excuse at all.
"Jack can come back and be very strong and help us finish the season well.
"If Abou Diaby comes back well and quickly we should, number-wise and quality-wise, be all right. That depends as well on the injuries we have in the next two or three months."