Arman Tsarukyan appeared to punch a fan as he made his walk to the Octagon at UFC 300.
Before fighting Charles Oliveira in a UFC lightweight eliminator, Tsarukyan clashed with a fan before entering the Octagon.
A video seems to show the UFC star throwing punches at a spectator before being dragged away by a Nevada commissioner.
As for the fight, Tsarukyan survived a scare in the first round as he escaped Oliveira's rear-naked choke before controlling the rest of the fight.
He landed a series of takedowns and opened up his opponent with a brutal elbow and survived another submission attempt during the closing stages of the fight.
Tsarukyan got the nod over Oliveira, claiming a split-decision victory to register his fourth straight win in the UFC.
He boasts wins over Damir Ismagulov, Joaquim Silva, Beneil Dariush and, of course, Oliveira since dropping a decision to Mateusz Gamrot.
The Armenian seems to be in line to fight UFC lightweight champion Islam Makhachev next following his big win at UFC 300.
Speaking at the post-fight press conference, he addressed the situation, saying: "He showed me f**k and wanted to punch me, and I wanted to punch him back.
"I’m from Russia, don’t do that please. Or I’m gonna to prison, in US."