Kick-off was delayed by an hour as thousands of Cologne fans tried to gain access to the Emirates, with many of the travelling supporters ending up in home sections of the ground.
When the match finally got underway, Arsenal fell behind to a sublime Jhon Cordoba lob which caught out David Ospina after just nine minutes.
The Gunners rallied after half-time with substitute Sead Kolasinac firing in an equaliser before Alexis Sanchez and Hector Bellerin added some gloss to the scoreline.
Scroll through the gallery above to see how the Arsenal players performed during their 3-1 win over Cologne.