Because of the coronavirus and the state's limit on large gatherings, it was canceled.
UFC's president says the fight is still on for April 18 but hasn't said where.
On Tuesday night, the New York Times reported the event will happen at Tachi Palace Casino Resort, near Lemoore.
On Wednesday, Kings County Sheriff David Robinson confirmed that report, adding that it will be a televised event and not open to the public.
ABC30 Legal Analyst Tony Capozzi says the state of California's stay at home order doesn't apply to Tachi Palace, part of the Santa Rosa Rancheria Tachi Tribe.
"The tribes have their casinos and it's on their tribal land," Capozzi said. "That tribal land is considered like a different country."
Last week, Kings County officials issued their own 'shelter in place' order for residents.
They say the tribe is its own sovereign nation and their order cannot be enforced on tribal land.
"Should the event proceed, we, of course, are optimistic that the Tribe follow all best practices in protecting any participants from spreading the disease," the officials said.
Tachi Palace has not responded to requests for comment.
They did temporarily close on March 20, and at that time said they would continue to follow guidance from health officials on COVID-19.
"There's still a medical danger here," Capozzi said. "These are two fighters going after each other. There's going to be sweat, there's going to be blood, there's going to be the doctors, there's going to be the referee. Those people are susceptible to COVID-19. So this is very dangerous. I don't think it's a good idea for the tribe to be pursuing this."
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