Sunday's FA Cup tie between West Brom and Wolves at The Hawthorns was interruped by disgraceful scenes of violence which were a throwback to a dark era for English football.
The Black Country clash was suspended after 79 minutes and resumed following a break as supporters ran on the pitch following violent clashes in the stands.
In the first meeting between these two rivals since 2012, the atmosphere was already fiery, but tensions boiled over after Matheus Cunha put Wolves 2-0 ahead in the 78th minute.
Shortly after Cunha's goal, fights broke out between rival fans in the corner of the Birmingham Road End and a number of supporters invaded the pitch.
Police and stewards sought to restore order and four announcements were made asking fans to return to their seats, but many remained on the pitch and the game could not be restarted.
It was decided that the players should return to their respective dressing rooms and in another message on the loudspeakers, fans were warned that the match would be abandonded of they did not leave the pitch.
After around half an hour, the players came back out and the match was resumed, but West Brom are set to face severe punishments following the ugly scenes, which saw one ban treated for a bloodied face.
West Brom defender Kyle Bartley was seen protecting a young child on the pitch at one point, while a ball boy was also hit by missiles being thrown at Wolves defender Matt Doherty.
Around 250 riot police were deployed for Sunday's derby and despite the intense atmosphere, there had been no sign of what was to follow until the violence erupted towards the end of the game.
After the players returned to the pitch, the match was concluded and Wolves saw out a 2-0 win which sees them take their place in the last 16.
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