Photos by Jason Merritt/Getty Images, John Locher/Associated Press

Gina Carano isn't a fighter. She hasn't been a fighter since 2010. And she lost her last fight.

If you're like me, your last memory of Gina Carano as a mixed martial artist was hoping referee Josh Rosenthal would have the heart to stop Cris Cyborg from beating her half to death.

This was five years ago, or nearly so, and Carano was undefeated going into the fight. She was considered an underdog to Justino (then Santos), but only slightly so.

That seems so very silly now, doesn't it? Hindsight is one of the more powerful tools in the human arsenal, but it seems unfathomable that Carano was given a better-than-remote betting chance of beating Cyborg.

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The fight played out exactly as it should have, with Cyborg mauling Carano as though she were a bear toying with its food. Rosenthal finally stepped in, and Carano heaved a sigh of relief. The rest of the world offered a prayer of thanks for her health and well-being. Cyborg was the new Strikeforce champion.

Carano? She never stepped in the cage again. She went to Hollywood as a budding action star. She made some action movies, and people made fun of her acting abilities, and she never quite developed the Hollywood career she wanted, so now she's toying with the idea of a return to the cage.

This time, it would be in the UFC, and it would be a big-money fight against Ronda Rousey, who is also a terrifying force of nature in her own right.

Carano hasn't competed since 2009. We don't even know if she's kept up her training over the past five years, though it is hard to imagine her giving it up completely. But still...five years is a very long time. Ring/cage rust is a very real thing, and if fighters who are away for 12 to 15 months are badly affected, you can bet that more than 60 months away from professional cagefighting will be a difficult thing to overcome, if not impossible.

There are actual deserving challengers on the roster.

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Remember Cat Zingano? She beat Miesha Tate to earn a shot at Rousey's title back in 2013. But then she had the temerity to injure herself in training, and the UFC nearly injured itself in its haste to replace Zingano with the more marketable Tate. And then Zingano suffered immense personal tragedy that kept her on the shelf even longer, which gave the UFC time to cast its eyes westward, toward Hollywood and Carano and beauty and fame and a million pay-per-view buys.

But Zingano is still here. She lost that title shot, of course, and now she has to fight at UFC 178 to earn it again. She may not earn it there, either, because there are Carano and Holly Holm, both of whom are likely ahead of Zingano in the pecking order.

Never mind that the only thing Zingano did to lose her original title shot was get injured and then go through unspeakable tragedy; she was out of the public eye for a year, and so she is shifted down the line, about to be bypassed by someone who hasn't competed in five years (and who lost her last fight).

Zingano is still more deserving than Carano. Holly Holm, despite never facing anything resembling top competition, is more deserving. Tate has lost twice to Rousey, and she's still more deserving. Every single fighter on the UFC women's bantamweight roster is more deserving, regardless of placement in the rankings.

This isn't about credibility; it's about looks and marketability.

Of course it is. There is literally zero ways to explain this one, other than "these are two gorgeous women and they're both actresses and they're both super famous and it's going to make a lot of money." Watching Dana White trying to explain his reasoning for giving Carano an immediate title shot—and watching him try to do so with a straight face—is one of the funnier things happening in mixed martial arts right now.

But because White is a promoter, he's doing his best. Even if his best makes him look silly.

But...

This is the most marketable fight the UFC can currently make.

There is no doubt that Rousey vs. Carano is the biggest fight the UFC has. Nothing else comes close, except perhaps Johny Hendricks defending his championship against a returning Georges St-Pierre, and I'm not sure that fight will ever happen.

Jeff Chiu/Associated Press

Promoted properly, Rousey vs. Carano will do more than one million pay-per-view buys. Guaranteed.

It won't approach UFC 100 levels, but it could be the second-biggest fight in company history. At the end of the day, the UFC is an entertainment company first, and it must worry about its profits. The UFC doesn't exist for the betterment of mixed martial arts; it exists because it is acutely aware of the bottom line.

The UFC will do whatever it can to increase that bottom line, even if it means pitting an actress who has not competed in a fight (and lost her last fight; we can't forget that little nugget, either) in five years against the most dominant champion on its roster.

From a sporting perspective, it is ludicrous that Cyborg remains on the sidelines, while Carano—whom she badly beat five years ago—waltzes back into the UFC and gets an immediate title shot. It's silly that Carano will bypass Zingano and Holm and everyone else on the roster. It makes zero sense.

But it makes dollars. Lots of them. Which is why, at the end of the day, you will see the fight happen. And though it seems counterintuitive, fights like this one are good for the sport. They extend the reach of the UFC. They make your friends tune in when they normally would bypass watching altogether. They stand out from the endless, ceaseless pack of similar UFC cards the UFC puts on these days.

They feel important. Which is why we watch, and it's why you'll be watching even if you say you won't.

Big fights are a big deal, and this is the biggest fight the UFC can make.