Bitter rivals Velez and Zrinjski, two teams split by an ethnic divide, recently played for the Bosnian Cup.  Visiting Velez scored a goal in extra time and as you might imagine, the fans of Zrinjski did not take it too well. The irrational spectators charged the field as the Velez team fled for their lives, running to the parking lot and the relative safety of the team bus. 

Even Philadelphia fans will have to admit that the backers of Zrinjski are pretty passionate.

Perhaps soccer needs more of this to gain popularity in the US.