Francis Coquelin has agreed terms with Valencia and his move to the Spanish side should be completed within the next 24 hours report French outlet RMC.
The midfielder has fallen out of favour this season, with just 156 minutes of Premier League action to his name, although he has featured regularly in the Europa League and Carabao Cup.
The potential move means he won’t play in tonight’s semi-final first leg against Chelsea, and he could become the first departure of the window.
The Gunners rejected an approach from West Ham, who are now said to be interested in teammate Mohamed Elneny, but it would be a stretch to let another midfield player leave with cover now even lighter in that area.
The club are still to decide over Man City’s £20m bid for Alexis Sanchez, and his involvement tonight – or not – could be telling in that regard.
Theo Walcott is another potential candidate to leave this month, with former club Southampton and Everton both interested.