Bradford City manager Phil Parkinson has vowed to punish the Bantams players involved in an ugly post-match fracas after Crawley's 2-1 win at Valley Parade.
Three Bradford players - Andrew Davies, Luke Oliver and goalkeeper Jon McLaughlin - and Crawley pair Kyle McFadzean and Claude Davis were shown red cards following the brawl.
Promotion-chasing Crawley gained a fourth successive win to inflict Bradford's first home defeat since November and keep the Bantams just four points above the relegation zone.
Crawley took a 54th minute lead when Leon Clarke headed in Scott Davies' free-kick. The Bantams responded on 72 minutes, Chris Dagnall heading home Kyel Reid's free-kick.
However, Crawley's lead was restored five minutes later, as Gary Alexander nodded past McLaughlin from a Scott Davies cross.
City boss Parkinson promised heavy fines to any of his players who threw punches, and said: "The referee seems very clear in his mind what went on and that is the reason he took the action he did in the dressing rooms.
"Both clubs have paid a heavy price. I can't believe this has happened. I have never been in a situation before where a ref has come into the dressing room, pulled players on one side and sent them off. He wouldn't allow me in there!
"I will look at the DVD and if any of my players are guilty of throwing punches they will pay heavy fines."
Crawley manager Steve Evans said: "I only saw the Bradford player Andrew Davies run towards my players and throw a punch. I think it was handbags, with a lot of pushing and shoving, but it was disappointing to see.
"If people have acted out of turn they need to be dealt with. It is a shame because it takes away from what was an outstanding performance "