"I can't predict exactly how long it will take because I'm not a doctor, but this is a significant matter and he will be unavailable for a while. Hopefully, it won't be for months, but we'll have to wait and see."
Arsenal, Premier League runners-up last season, visit reigning champions Manchester City on Sunday.
Listen to the latest songs, only on JioSaavn.com
The Gunners beat local rivals Tottenham 1-0 last weekend to sit second in the early Premier League table, two points behind Man City.
(This story has not been edited by staff and is auto-generated from a syndicated feed.)