Trouble started with hundreds of Schalke fans arriving in Dortmund, lighting flares and overturning trash cans as they walked to the stadium and fighting with rival fans. Both fanbases then turned their hostility towards police.
Police used plenty of pepper spray and a water cannon to separate fans, while mounted police were attacked with stones. Police said fans had also destroyed a snack bar near the stadium, breaking it up and using parts of it as missiles.
There were several minor injuries and at least 150 rioters came into police custody.
Around 1,000 police officers were on duty, four times the usual number for a typical matchday.
As for the game, Schalke would win the Ruhr Derby 2-1.