It took the shine off a great day for the club.
Every club has one player that personifies the passion, love and devotion that fans have for their team, and in Millwall's case, that player is Steve Morison.
Very few players know what makes Millwall tick quite like their goalscoring hero as the Lions secured promotion to the Championship.
This season, Morison has scored 18 goals in all competitions, but none have been more important than his dramatic winner against Bradford this afternoon.
Well, he also scored a brace against Scunthorpe United in their play-off semi-final, but right now, Millwall fans and players must be feeling absolutely ecstatic.
This being said, the match winner was far from impressed as he watched his own supporters invade the pitch, telling Sky Sports: “The fans have ruined it for me at the moment. I can’t celebrate. [But] it’s fantastic to be back in the Championship. We’ll have a good crack.”
Millwall manager Neil Harris also spoke about the incident, but he was a bit more relaxed about the issue. "They came on in good spirit. Do we want them on the pitch? No, not at the home of English football. But they came to celebrate with their team," he said.
Bradford manager Stuart McCall hit out, saying: "Wembley have to learn from this. Everyone in the place knew they were coming on. I was close to clocking a couple. They were in my face. I was verbally assaulted, not physically. Why can't they just enjoy their moment?"
Take a look at the pitch invasion below along with some of the online reaction.
https://twitter.com/MrTomMcDermott/status/865961441379180544
https://twitter.com/Perriesherman/status/865960030281117696
https://twitter.com/tclansee/status/865960598282153986
https://twitter.com/helenwardie10/status/865960234187141127
