came from behind to beat Cologne in their delayed Europa League opener against a backdrop of crowd trouble at the Emirates Stadium.
Kick-off was delayed by an hour as ticketless away supporters attempted to enter the ground, with plenty of Cologne fans sat in among the home section when the tie finally got under way, with the Gunners eventually winning 3-1.
Four arrests were made on suspicion of public order offences as extra police were deployed to the scene.
On the pitch, Arsene Wenger's much-changed side showed determination to fight back from Jhon Cordoba's early 40-yard strike and seal three points.