Amanda Nunes became the first UFC fighter to defend a championship belt while holding titles in two weight classes, earning a dominant unanimous decision over featherweight contender Felicia Spencer at UFC 250.
Former bantamweight champion Cody Garbrandt also knocked out Raphael Assunção an instant before the second-round bell in the co-main event at a fan-free gym on the UFC's corporate campus in Las Vegas.
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UFC 250 was the second event held at the UFC Apex gym in the promotion's hometown since its resumption in competition amid the coronavirus pandemic. The Apex octagon is 25 feet in diameter instead of the typical 30 feet, and those close quarters resulted in several entertaining finishes, including spectacular knockouts by Garbrandt and fellow bantamweight star "Suga" Sean O'Malley.
Nunes (20-4), widely considered the greatest female fighter in mixed martial arts history, is the UFC's champion of the bantamweight and featherweight divisions.
While Nunes' dominance was tested in her last bout against bantamweight Germaine De Randamie in December, the relatively inexperienced Spencer (8-2) provided little challenge to the champ, other than the remote possibility of breaking her hands in repeated collisions with Spencer's face.
Nunes battered the slower Spencer with her fearsome striking power from the start, cutting the challenger's face and later sending her mouthpiece flying away during the third round. Spencer had a nasty hematoma growing on her forehead after the fourth round.
Nunes comfortably defended her featherweight belt for the first time since taking it from Cris "Cyborg" Justino in December 2018. She has defended the bantamweight belt five times since 2016.
"That was my goal, defend my two belts at the same time. I defended both belts, I'm the greatest. I'm so happy right now, I don't know what is next," Nunes said after the fight.
Garbrandt (12-3) had lost three straight fights before this impressive performance ended with a right cross that knocked out Assunção in the final second of the second round. Garbrandt retreated to the fence, dodged Assunção's right hand and landed a perfect shot to the face, sending Assunção tumbling backward and face-first to the canvas.
The win was Garbrandt's first since December 2016, when he beat Dominick Cruz for the 135-pound title.
O'Malley (12-0) opened the pay-per-view portion of UFC 250 with a vicious one-punch knockout of veteran Eddie Wineland just 1:54 into their bout.
O'Malley's right hand to the jaw deposited Wineland flat on his back with his hands still raised. O'Malley imperiously walked away from his single punch before the senseless Wineland or the referee knew what happened.
"When you're as fast and accurate as I am, I'm gonna land first and I'm going to land early," O'Malley said. "And I landed on the button."
Later, Aljamain Sterling rendered Cory Sandhagen unconscious with a rear naked choke just 88 seconds into a fight to determine the next contender for the bantamweight title. Sterling (19-3), who has five straight victories, swiftly locked in a full body triangle and a deep choke to finish Sandhagen, who tapped out right before going to sleep.
Light heavyweight Devin Clark took a knee with his fist raised in the air during his pre-fight introduction from Bruce Buffer. Clark then earned a unanimous-decision victory over previously unbeaten prospect Alonzo Menifield, persevering through a left eye closed by punches.
Clark and teammate Jon Jones spent time on the streets of Albuquerque last weekend, speaking to protesters and helping in the cleanup effort for property damage.
Clark didn't speak to the media after his fight, instead heading to a hospital for immediate care.
But Sterling spoke out in support of the widespread protests following the death of George Floyd in his post-fight interview.
"The world is in shambles right now, especially America," Sterling said. "We've got a lot going on in this country. It's a great country, but there's a lot of things that need to be changed, especially the injustices happening to minorities all across America. This one is for everybody back home fighting the good fight, protesting. I support you guys. I'm with you guys all the way."
Featherweight Cody Stamann earned a dominant decision over Brian Kelleher just 10 days after the death of Stamann's 18-year-old brother, Jacob.
"It's been real hard," said Stamann, who was visibly emotional in the cage. "I've been fighting tears all day. I had to buckle up and be a man and get this done for my family, for myself."
The UFC led North American sports' return last month with three shows in Florida. President Dana White is determined to hold near-weekly shows going forward, and he still intends to stage fights this summer on a private island dubbed "Fight Island."
Although White has been secretive about the location where he will stage bouts between fighters unable to reach the U.S. due to coronavirus travel restrictions, lightweight Herbert Burns let slip that Fight Island is in Abu Dhabi after he beat Evan Dunham in the opening bout of UFC 250.