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On a brisk May night twelve years ago, Cristiane Santos walked to a ring in her hometown of Curitiba, Brazil. It was her first professional fight. She lost by submission, tapping out to a kneebar in just under two minutes.

Mixed martial arts is full of stories like this. People fight once or twice and lose and decide it's not for them, and then they walk away and pursue some other, more normal career. Santos' story could've ended that night at Show Fight 2.

Instead, she returned later that year and won her second fight. And her third. It has been twelve years, and she still hasn't lost another fight. And truthfully, it has been a long time since anybody even entertained the notion that she might lose again.

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When was the last time you seriously gave a Cyborg opponent a real shot at winning? For me, it was probably the fight against Gina Carano in 2009. Cyborg was mostly unknown at that point and Carano, forever the apple of all our eyes, was a heavy fan favorite. Cyborg thrashed her so badly that Carano never returned to mixed martial arts, opting to pursue other, less-violent career paths.

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I vaguely remember thinking Marloes Coenen had a chance of winning, at least the first time she faced Cyborg, but that pretty much went the same way the Carano fight did, with the only real difference being the greater extent of the beating.

Cyborg fights have become something of a routine. We always know what's going to happen, and we know it's going to be physical and violent and ugly and uncomfortable to watch.

She is dominant in a more visceral way than other dominant champions like Georges St-Pierre or Demetrious Johnson. Those men are supremely skilled and entertaining; watching them is a pleasure. Watching Cyborg is like watching a tornado carving through a small Midwestern town. We know what's coming. We've seen it before. We still can't turn away.

UFC 219 will be different. For the first time in forever and a day, Cyborg is facing an opponent who has a legitimate chance of not just lasting to the final bell.

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Holly Holm, the former world champion boxer, vaulted to stardom two years ago with her brutal knockout of Ronda Rousey to capture the UFC bantamweight title. Much like Cyborg did in sending Carano packing, Holm essentially ended Rousey's career that night in Australia. Rousey didn't retire after that loss, but when she returned a year later to face Amanda Nunes, she was a shadow of a shell of her former self. The raging fire long present in her eyes was gone. Holm had extinguished it, just as Cyborg rattled Carano to her core.

Holm will step into the Octagon to vie for Cyborg's featherweight championship. It is a belt and a division essentially created as a way to keep Cyborg in the UFC and headlining pay-per-view events. The event-buying public seems perfectly content, at least for now, to watch Cyborg mow through hapless competition just as she did in the years leading up to her big turn in the UFC.

But Holm is no patsy.

There is a case to be made that this is the best fight in the history of women's mixed martial arts. It won't be the biggest financial success; Rousey is still the queen of that department even in the midst of her quasi-retirement from the sport.

But from a quality, skill and technical perspective, there is no better match-up to be made at this point in time. Holm has been underwhelming since the night she beat Rousey, but she is still far and away the best counterpart for Cyborg, and will easily be the biggest win of Cyborg's career should she prevail.

The same goes for Holm. Critics will point at the Rousey knockout as the high point for Holm's MMA tenure. But in truth, Holm was always more than a tough out for Rousey; Holm had an overwhelming striking advantage that we all overlooked because we were blinded by Rousey's stunning pad-hitting and shadowboxing. In reality, Rousey was and is an atrocious and deficient striker who may have been misled by her coach to believe she was far better than she actually was.

Andy Brownbill/Associated Press

If Holm is able to beat Cyborg, especially in the same manner she beat Rousey, it will be a far greater accomplishment than her win over Rousey. Beating Cyborg means you must be a better striker, but even more it means you must endure. Cyborg's initial onslaught overwhelms opponents like a dense morning fog, wrapping them on all sides; Holm will need to continually look for the light on the other side.

But she can do it. She can endure, and she can beat Cyborg. She has a legitimate chance of beating the most terrifying woman on the planet. And of course, Cyborg has a chance of turning Holm into nothing more than another line entry on a long list of overwhelmed opponents.

There is so much we can find out about both women and their skills and spirit. We'll find out if Holm was a one-shot wonder, or if she truly is the breathtaking prospect many of us thought she'd be when she transitioned from boxing to mixed martial arts.

And we'll find out if Cyborg is indeed capable of being challenged, or if she's just a fighter so advanced that it seems like she's in the wrong decade, or perhaps the wrong millennium.