Gunners boss Arsene Wenger said: "The Champions League qualifiers are our biggest games of the season - but we have left a big squad at home and I am not left with many options.
"Basically, it is a choice of a young player or an even younger one.
"As well as Fabregas we are without Toure, Senderos, Nasri, Diaby, Rosicky, Eduardo, Song and Amaury Bischoff.
"I have never known such a problematic start to a season.
"The trouble is, when you have to play Champions League qualifiers so early, you push players and they get injuries, which is what has happened."