The Na Koa MMA Podcast was on the scene and has a report of the incident:
The brawl was apparently about a young lady now dating the UFC 155 lb fighter Donald Cerrone who used to date main event fighter of the evening Marcus Sursa. Comments were exchanged after Sursa returned from a trip to the rest room and Cerrone was over seeing the warm-ups of several Jackson MMA fighters on the card this night, some words were exchanged by the two and then a shove followed by Cerrone throwing a punch causing a laceration on the eye of Sursa, he responded with a punch cutting the lip of Cerrone. All told, Sursa was now out of the main event tonight against Buddy Roberts of Reno, NV due to the cut he suffered.
Now, this is one account of what happened, but if this is what happened, it is absolutely unacceptable behavior by Cerrone, who, less than two months ago, got in hot water for saying he wanted to kill rival Jamie Varner, among other things. Once again, Cerrone has shown extremely poor judgment and this is even more inexcusable than his prior actions. Not only do his actions affect himself, but also Sursa and then Roberts, who was harmed and didn't have anything to do with it. There's a reason people are called professional fighters. Emphasis on professional. Cerrone is scheduled to face Chris Horodecki at WEC 53 in December. If I'm Zuffa, I take a hard look at whether that's a fight I really want to put on and if Cerrone is a fighter I really want to employ.
I'd love to hear all sides of the story, but this looks very, very poor for Cerrone.