As the final whistle blew inside the AFAS Stadion, Alkmaar, things got ugly.
West Ham had reached their first major European final since 1976 after winning the Europa Conference League semi-final second leg.
Then a group of AZ Alkmaar fans attacked an area in which the London team's friends and family were watching the match from. West Ham players confronted them with some heading into the stands.
Here's how the chaotic scenes unfolded in 85 seconds.