Two fighters took to the cage for the UFC 207 main event, two more for the co-main event on Friday night in Las Vegas. Of the four, three performed like champions. The other was Ronda Rousey.

This night rightfully belonged to Amanda Nunes, who defended her women’s bantamweight championship for the first time with a ferocious 48-second technical knockout of the ghost of the Rousey we used to know.

[UFC 207: Rousey suffers brutal loss at hands of defending champ Nunes]

The night also belonged to Cody Garbrandt, who rose from middling contender to men’s bantamweight champ with a stunningly poised performance that ended the reign — and 13-fight winning streak — of Dominick Cruz. “The Dominator” was dominated in a unanimous decision.

Cody Garbrandt, right, ended Dominick Cruz’s reign. (John Locher/Associated Press)

The night belonged to Cruz, too, for the way he handled himself. After losing for the first time 10 years, he set aside the acrimony that had boiled over prior to the fight and offered congratulations to Garbrandt (11-0), then spoke eloquently about the ups and downs of being a champion. His belt may be gone, but Cruz’s self-awareness and perspective on sports remain intact.

By handling his defeat so gracefully, Cruz (22-2) far outclassed Rousey, who after her beating sulked her way out of the cage and disappeared into the night, with not a word for her fans or her conqueror. “Rowdy Ronda” used to be known for being graceless in victory. Only one part of that has changed, and it isn’t the graceless part.

The spotlight that always seems to find Rousey used to shine on her glowingly, back when she was vanquishing opponents in seconds. But on Friday night the bright lights only exposed the glaring weaknesses in her fight game. Returning from a 13-month layoff following last year’s highlight-reel knockout loss to Holly Holm, and after charging into the octagon looking like the Rowdy Ronda of old, Rousey was passive and tentative and feeble from the start. Nunes connected with a crisp jab just 10 seconds in, and from that moment, Rousey looked less like a star in the spotlight than a deer in the headlights.

“Forget Ronda Rousey,” Nunes told the 18,533 assembled at T-Mobile Arena, the largest crowd ever for a UFC event in Vegas. “C’mon, guys, bull---- Ronda Rousey. Now she’s going to retire and do movies. She already has a lot of money.”

[Nunes trolls Rousey on Twitter after victory at UFC 207]

That would be a wise career move. Like the post-Buster Douglas version of Mike Tyson, the 29-year-old Rousey (12-2) has lost her swagger. Perhaps she can rediscover it on the silver screen.

Nunes (14-4) deserves all of the accolades bestowed upon a conquering heroine. But the 28-year-old Brazilian, the UFC’s first openly gay champion, readily acknowledged that she got a big assist from an unlikely ally. Rousey’s embattled trainer, Edmond Tarverdyan, has taken an Olympic bronze medalist judoka and molded her into an athlete with no sense of her strengths and weaknesses.

“She thinks she’s a boxer,” Nunes said of Rousey. Tarverdyan “put this thing in her head and made the girl believe in that. I don’t know why he did that. She’s great at judo, but he put some crazy thing about his boxing, and her head started going down.”

So while Nunes can be commended for landing 27 strikes (to Rousey’s seven) during the brief fight, according to statistics compiled by FightMetric.com, the champ’s accuracy was significantly augmented by an utter lack of head movement by her sitting-duck opponent. Rousey doesn’t need to put herself through that again.

The UFC surely wouldn’t mind if she wants more, of course. When the entertainment behemoth WME-IMG bought the fight promotion over the summer for an unfathomable $4 billion, the deal was built on star power. Conor McGregor was setting records as a pay-per-view draw. Brock Lesnar was returning to the cage. And Rousey was angling to get back in, too.

But now? Lesnar popped for performance-enhancing drugs and is gone. Rousey is a broken figure, with one foot out the door even before Friday night. And McGregor announced last month that he’s taking several months off while waiting for his partner to give birth to their first child. Related to that, the Irishman noted that in his quest to set his growing family up for life, he wants an equity stake in the UFC. He said he was disappointed the new UFC brass has not come to Dublin to meet with him.

After the events of Friday night, when the company’s only other luminary fizzled out and a recognizable longtime champion was beaten by a young gun barely recognized beyond the die-hards, the UFC must be wondering where its star power has gone all of a sudden.

It’s gone shopping for prams on O’Connell Street. Fuel up the private jet, set a course for Dublin and bring the checkbook.