Francis Coquelin's injury was the only negative note for Arsenal in the 3-0 win over Chelsea last weekend.
The French midfielder left the Emirates with a bracearound his knee and he will undergo a scan today to know the extent of his injury.
Gunners manager Arsene Wenger stated that it's a similar injury to the one Coquelin suffered last year, so the player could be out for four months, until January.
This fact can give new signing Granit Xhaka the space he needs to progress in the Premier League side.
Source: transfermarketweb.com