Emirates club rocked by pre-season injuries.
Arsenal have been dealt another injury blow with the news midfielder Abou Diaby will miss the first 10 weeks of the season.
The 25-year-old has undergone an ankle operation that has disrupted his pre-season training plans.
The France international injured the joint last season and has missed the tours to Asia and Germany.
Diaby will be sidelined until September and will Premier League games against Newcastle, Liverpool and Manchester United, as well as the Champions League play-off.
It is a huge blow for Gunners boss Arsene Wenger who could be short of options in central midfield.
Denilson has gone on-loan to Sao Paulo while the futures of Cesc Fabregas and Samir Nasri continue to hang in the balance.
“Abou had ankle surgery during the break,” Wenger told the club’s website.
“Normally he should be back eight to 10 weeks after his surgery, which means the end of August.”
The injury for Diaby comes on the back of both Conor Henderson and Theo Walcott returning early from Germany with knocks.
Henderson, 19, has damaged his cruciate ligaments and will be out for at least six months.
Walcott, 22, has had a scan on an ankle injury but their are no plans he needs surgery and will be monitored closely.