After the fight, Pearson took heat from the partisan crowd for refusing to shake the Australian native's hand.
Apparently, the beef stems from an off-camera incident that occurred between Sotiropoulos and Erin Beach, Pearson's boxing coach, during filming for The Ultimate Fighter: Team Australia vs. Team U.K.
According to Pearson, Sotiropoulos confronted Beach about comments made on Twitter, but instead of squashing the issue like a professional, the Aussie threw a punch. After being struck, Beach defended himself and knocked out Sotiropoulos.
MMAJunkie caught up with Pearson to get his thoughts on the alleged incident:
That's why I said I lost all respect for him, and that's why I didn't shake his hands afterward. That's why I'm not his friend now – because he acted unprofessional.
Sotiropoulos and Pearson served as opposing coaches on the second international installment of TUF, and Beach was brought in to help with the coaching for Team Pearson.
The incident drew the ire of UFC President Dana White, who wasn't too pleased to find out one of his fighters was knocked unconscious during a random physical altercation.
What if Sotiropoulos or Beach were seriously injured? The incident also put the entire UFC on FX 6 fight card in jeopardy.
Pearson recalls his entire team being called into a room for a phone interview with an incredibly upset White on the other end:
Dana chewed our heads off. George was acting unprofessional. I get paid to fight; I don't fight in the streets for free.
Sotiropoulos may want to stay off Twitter.
The loss to Pearson marks his third straight in the UFC. The recent falloff has been steep for Sotiropoulos, who was riding an eight-fight win streak.
His camp has yet to give a response on the alleged incident.