Amanda Nunes is celebrating a special UFC first…

The 28-year-old Brazilian mixed martial artist pulled off an upset win over Miesha Tate in the main event of UFC 200.

With the win, Nunes is now the first openly gay champion in the history of the Ultimate Fighting Championship.

She clinched the belt by dominating Tate with a fierce early flurry, then causing the bantamweight champion to tap out after just 3 minutes, 18 seconds.

“This is amazing,” Nunes said, when asked by USA TODAY Sports about the significance of her achievement. Nunes has been in a relationship with partner Nina Ansaroff, also a UFC fighter, for four years. “I am so happy in my life,” she added.

During the endless months of planning and plotting and trying to stack the show with as many famous names as possible, the hierarchy at the UFC probably didn’t figure on their signature event ending with an upset win from a little-known fighter.

Nunes has around 25,000 followers on Twitter, a number that jumped greatly in the hours after she wrested the belt from Tate, the third such change of bantamweight hardware since November.

“To have our very first openly gay champion shows you how far this sport has come,” UFC vice president of public relations Dave Sholler said. “Amanda is an incredible ambassador. When you talk about all the great moments, having Amanda carry the flag literally and figuratively for the gay community is a seminal moment for our sport.”

The UFC is not an organization that immediately springs to mind when you think about progressiveness. Middleweight champion Michael Bisping uttered a slur at opponent Luke Rockhold after his win at UFC 199 last month, though he immediately retracted it.

When transgender fighter Fallon Fox revealed she had been born a man in 2013, heavyweight Matt Mitrione – then with the UFC – branded her a “sick, sociopathic, disgusting freak” and was given a temporary suspension.

In past years, fighters have used epithets related to homosexuality to taunt rivals. In truth, such behavior has not been entirely eliminated.

However, UFC president Dana White said in 2011 that he hoped that any gay UFC fighters would feel empowered and safe enough to come out. More recently, the company has launched an initiative called “We Are All Fighters,” aimed at promoting understanding and to benefit an LGBTQ community organization in southern Nevada.

That cause now has a powerful figurehead in the quirky, humorous and thoroughly charming Nunes, whose devastating combat skills are at odds with her regular persona.

“It is huge,” Ansaroff, a UFC strawweight with a 6-5 record, told USA TODAY Sports minutes after her partner’s triumph. “Not so much for us or the fact we are trying to get recognition as a gay couple, but for the human race as it is. People are people. They could be your neighbor, or your next UFC champion. Treat everybody the same.”

Ansaroff and Nunes live openly, regularly posting affectionate messages and photographs on social media.

“(Amanda) is pretty much the exact opposite of what everyone thinks about her,” Ansaroff said. “When I first met her, I thought, ‘This lady is crazy.’ But she is the biggest sweetheart, she will do anything for her loved ones. She always likes to have fun. The only time she is serious is when that cage door pops.”

Nunes is now part of a women’s bantamweight division that brings all kinds of intrigue. She now sits alongside Ronda Rousey, Holly Holm and Tate as part of a four-pronged collective at the top of the pile.

A bout between any one of the group would likely be pay-per-view headlining material. The situation should provide a long series of battles before it shakes out anything decisive — depending on when Rousey returns.

“Now I am champion,” Nunes said. “Next will be whatever, whoever, they decide to put against me. I am going to enjoy being champion.”