Timber, who was signed for 40 million euros from Ajax last month, hobbled off the pitch holding the back of his knee in the first half of Arsenal's season-opening win over Nottingham Forest on Saturday.

"We can confirm that Jurrien Timber has sustained an injury to his anterior cruciate ligament in his right knee," Arsenal said in a statement. "Jurrien will undergo surgery in the coming days and will be out of action for a period of time.

"The support and expertise from our medical team and everyone at the club will now be focussed on Jurrien’s rehabilitation programme, to ensure he recovers well and is back playing as soon as possible."

Arsenal next travel to face Crystal Palace on Monday.