Longtime mixed martial arts referee Mario Yamasaki stands behind his decision during the Michael Chiesa vs. Kevin Lee lightweight bout at UFC Fight Night 112 in June despite Chiesa’s criticism.

Lee locked in a rear-naked choke late in the first round, and Yamasaki stopped the contest before Chiesa tapped. “Maverick" appealed with the Oklahoma State Athletic Commission (OSAC), but they denied his request to overturn the loss to a no-contest.

"I saw the moment he went out,” Yamasaki told MMA Fighting. "He can complain, but there’s no other way. The athletic commission already reviewed it, there’s nothing more to say. … (The commission) contacted me, I explained what I saw and he explains what he saw and felt. They watched the fight in slow motion and didn’t find anything wrong.

"It would have been a lot easier to let him go out longer, but my job is to defend his integrity when he's no longer doing it for himself."

Upset with the loss that snapped a three-fight winning streak in the UFC, Chiesa challenged Yamasaki to a grappling match during the upcoming Onnit Invitational on Sept. 30.

“I would like to test his fifth degree black belt in a friendly grappling match and let’s see if he’s what he says he is,” Chiesa told Ariel Helwani on Monday’s edition of The MMA Hour. "And I’m not saying it in a hostile way, I’m saying, ‘hey, if you’re a fifth degree black belt, you should back up for the decisions you made.’ As a martial artist myself, that’s my open challenge to him, to headline Onnit Invitational on Sept. 30.”

Yamasaki questions the UFC fighter’s intentions with the challenge. Yet, he responded with another suggestion.

"I’m 53 years old, I don’t train anymore, how am I going to do this?” Yamasaki said. "And what’s the point of him fighting me? What would that change? What does he want to prove? It’s childish. Even if he catches me or if I catch him, that won’t change anything that happened in his fight. What is he trying to prove?”

"If he gives me some time to train, I’d grapple with him,” he added. "Tell him to come to my academy, no problem. I have 10 academies in the United States, he can come any time he wants.”

Asked about the Sept. 30 date, Yamasaki says Chiesa just wants media attention.

"What is he trying to prove? That’s what I wanna know,” the referee said. "What would that change? He wants media, and he already had media."