GLENDALE, Ariz. — As the lights dimmed inside Gila River Arena while Israel Adesanya and Marvin Vettori circled to the center of the octagon, a fan screamed a request to the Ultimate Fighting Championship’s middleweight champion.
“Israel, I have $7K on this,” the fan exclaimed, referring to a bet he had made of $7,000. “Take his head off.”
Adesanya delivered for many gamblers by retaining the 185-pound belt when he beat Vettori, the Italian challenger, in a unanimous decision.
In the closing seconds of the fifth round, as Vettori grappled with Adesanya against the cage, Adesanya laughed and bellowed fake cries of pain. While he waited for the referee to raise his hand, he playfully smiled and crossed his fingers, as if he did not know the obvious outcome.
His personality and charm atop the main event of the U.F.C. 263 card allowed the company to fill 17,208 seats, generating more than $4.2 million in ticket sales, a record for the venue. Adesanya’s allure and his performance give the U.F.C. and its fans something they have not had in recent years among mainstream mixed martial arts stars: dependability.
Others competed on Saturday night in the second card the U.F.C. hosted in the United States this year without any coronavirus-related restrictions. Brandon Moreno became the first Mexican-born U.F.C. champion when he upset the flyweight champion Deiveson Figueiredo via submission by slithering onto his back and wrapping his neck in a chokehold. Nate Diaz, a fan favorite who entered the U.F.C. in 2007, lost to Leon Edwards, a strong welterweight contender, in an unconventional five-round, nontitle fight.
But the night revolved around Adesanya, who cemented himself as one of the promotion’s front-facing athletes.
“It’s almost like he gets better every time,” Dana White, the president of the U.F.C., said. “Adesanya has become a bad-ass champion for us.”
Adesanya, who is nicknamed The Last Stylebender, has incorporated anime cartoon references and dancing into his fighting style and his persona. Throughout the week leading up to the fight, fans in the Phoenix area overwhelmingly supported him compared with Vettori, through deafening cheers. On Saturday, he further exaggerated his antics by walking toward the octagon wearing a decorative face mask and straw hat. He chuckled when thinking about doing a “normal walkout.”
“That’s not me,” Adesanya said. “That’s not me authentically expressing myself.”
Known for his precise striking, Adesanya defended well against Vettori’s takedowns and countered most of his attacks. He wobbled Vettori’s base frequently by chopping his legs with kicks.
The two men first clashed in 2018 in the same arena, and Adesanya won by a split decision. In the rematch, he removed any lingering doubts. He remains unbeaten in his division, and his only loss came when he moved to light heavyweight to try winning belts in two weight classes.
Still, in recent years, stars who have been heavily marketed by the U.F.C. have slipped, both because of fights and because of outside circumstances.
Ronda Rousey, a pioneer in women’s mixed martial arts, defended her bantamweight title six times, all by dominating submission or knockout finishes. Mainstream stardom quickly followed.
But after Holly Holm landed a devastating head kick and defeated Rousey in 2015, she secluded herself and her confidence clearly drained. She soon retired after her second consecutive loss, to Amanda Nunes, a fight she took after a yearlong absence.
Conor McGregor, by far the most-popular and the highest-earning fighter in the promotion’s history, rose to prominence through a powerful left hand and persistent trash-talking that frustrated his opponents. He became the first athlete in U.F.C. history to hold two belts simultaneously, winning the featherweight and lightweight championships through knockouts and prompting others to chase similar dual-belt dreams.
A crossover boxing match with Floyd Mayweather in 2017 profited McGregor a guaranteed $30 million, and he has fought only three times in the octagon since. He is scheduled to headline U.F.C. 264 in a trilogy bout against Dustin Poirier on July 10 in Las Vegas, a fight that the U.F.C. is marketing as its biggest event this year.
McGregor has also had legal troubles. He pleaded guilty to assault for punching a man in 2019 at a bar in Ireland and took a plea deal for throwing a cart at a bus carrying U.F.C. fighters in Brooklyn in 2018. In January, McGregor was sued in Ireland by a woman who claimed he raped her in 2018, an accusation he has denied.
White said Adesanya approached him in the week leading up to the Vettori fight and asked to compete again in October. Saturday was the sixth time he headlined a card, and he has fought at least twice every year since joining the promotion. White said he would most likely next fight Robert Whittaker, whom Adesanya beat in 2019.
“I don’t wait around like the rest of these guys, the rest of these champions who talk about being active,” Adesanya said. “I don’t talk about it — I just do it.”
Three months ago, he moved to the light heavyweight division, attempting to capture that belt, too. But he lost to the champion Jan Blachowicz — the first loss in Adesanya’s professional career. Still, he said the moment motivated him rather than serving as a deterrent.
“How you grow is you learn from your mistakes, you go back to the drawing board, you improve and you become better from them,” Adesanya said.
Moreno, of Tijuana, adjusted from his shortcomings, too. His fight against Figueiredo served as a rematch from December 2020, when the two 125-pound men battled to a draw.
As White laid the belt on Moreno’s left shoulder, Moreno screamed as his family rejoiced. His infant daughter couldn’t hear much of it, though, because she wore pink protective headphones.
“I’m doing the correct thing to put mixed martial arts in other places,” Moreno said. “I’m making history.”
The skin above Diaz’s left eye seeped with blood and sweat at the end of the third round of his 170-pound bout, a result of the battering that Edwards delivered throughout much of the fight. But Diaz seemed to enjoy the contest, playfully turning his back and taunting Edwards.
With one minute remaining in the final round, Diaz landed a straight left jab, dazing Edwards. He tried to apply pressure with punches, but Edwards made it through the rest of the fight. Afterward, as he did earlier in the week, Diaz smoked marijuana during the news conference.
“To be dominant in a fight and then get caught with a shot out of the blue, I was like, ‘What?’” Edwards said. “Nate is a legend, he has been in the sport a long time and he knows how to ride his shots.”