The Unified Rules of mixed martial arts prohibit a fighter from excess grease on the body.
"The excessive use of grease or any other foreign substance may not be used on the face or body of an unarmed combatant. The referees or the Commission’s representative in charge shall cause any excessive grease or foreign substance to be removed."
In practice, all grease is banned from a fighter's body, as it is advantageous to the striker.
After Cortney Casey lost to Pearl Gonzalez at XFC 26 for the promotion’s first women’s flyweight championship, she is filing an appeal with the Tennessee Athletic Commission, charging that Gonzalez's pray tan ammounted to greasing.
“I want a rematch, and I think it’d be a great fight,” said Casey to MMA Junkie. “We did three rounds of amazing work, and it was a great show, and it was a great fight. But I can’t live with the fact that someone had a banned substance on them and that I couldn’t implement my game plan because of that substance.
“I just want to have a fair fight. And like I said, I wasn’t able to do what I needed to do as a submission fighter because of the tanning oil.”
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