Referee Mario Yamasaki called an end to the UFC Fight Night Oklahoma City main event declaring Kevin Lee the winner over Michael Chiesa by rear-naked choke submission in the opening round of their grudge match. 

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Chiesa, however, did not appear to submit or pass out from the hold before the fight was called, leaving the end of the event in controversy.

Lee for his part believes the fight was over anyway.

“You can see he’s fighting the choke," Lee said after the event.  "I switch from palm to palm; as soon as I do, his arms go limp.”

“Mario’s a very experienced ref, he saw it and stopped the fight. If he wouldn’t have, there was still 45 seconds left in the fight. I don’t see what the controversy is about. It wasn’t like I was going to let go.”

Chiesa on the other hand, was not impressed with Yamasaki's work.

"Mario Yamasaki should just crawl in a hole and never step inside of any type of professional mixed martial arts event," Chiesa said after the event. "He should never officiate, ever again."

UFC President Dana White also posted a comment critical of Yamasaki on his Instagram page.

In the co-main event, Tim Boetsch earned a second round TKO victory over former champion Johny Hendricks, stunning him with a head kick and following it up with scoring punches to finish the fight.