No media darling: Nick Diaz hopes to use rough edges to grind up champion Georges St-Pierre

Most fighters find out far too late that the real money in fighting comes not from their paychecks but from what they can earn from endorsement contracts.

Georges St-Pierre, the UFC's well-heeled welterweight champion, probably made more money in 2012 from endorsements alone than 98 percent of mixed martial arts fighters made in purse money. St-Pierre is sponsored by mainstream blue-chip companies such as Coca-Cola, Gatorade, Under Armour and Bacardi, sponsors that essentially are out of reach for the majority of his peers.

It's great work, if you can get it.

To this point, Nick Diaz hasn't been able to get it. Diaz, who will challenge St-Pierre for the belt in the main event of UFC 158 on Saturday at the Bell Centre in Montreal, has sweat and bled for every cent he's earned. Diaz has become the sport's anti-hero, even if it's a role he'd rather not have.

Much to his chagrin, he's been cast as the guy who soccer moms curse out at traffic lights.

Diaz's life is a polar opposite of the prim and proper St-Pierre's. During a must-be-heard-to-be-believed rant on a conference call, Diaz talked about being hated and how, indeed, a soccer mom let him have it while both were waiting at a red light.

Speaking directly to St-Pierre, Diaz said, "Check it out [expletive], I pulled up to a stop light the other day and some [expletive] 40-year-old lady, some soccer mom, sticks her head out the window and she's like, 'I hope GSP beats your [expletive].' We're in [expletive] Lodi, [Calif.] [expletive]. I'm like, 'Are you serious?' We are in the bull's-eye right now. You hope to beat my [expletive]? That's [expletive] wonderful.

"I'm living in a [expletive] small town full of people that hate me over here and, you know, I'm trying to [expletive]; I'm trying to [expletive] work my way up into a fight and now I'm the most disrespectful piece of [expletive] person that walks the earth and I deserve to have my [expletive] beat, that I deserve to have the [expletive] beat out of me and I'm just this disgusting person."

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Diaz hasn't been the most warm and cuddly guy to deal with and he goes off on so many tangents that it's hard to sometimes follow his thoughts.

St-Pierre talks of a dark place in his mind, but Diaz was born into that kind of dark place. For the most part, he's never really left it.

The champion insists he's come from rough beginnings, as well, but he figured out early how to play the game.

Of course, St-Pierre started with advantages that most of us can only dream of having. He's got a model's good looks and the kind of genetics that have given him a near-perfect body.

He's a brilliant talent who has worked maniacally to exploit it. And he learned early on that to appeal to the mainstream, he had to smile and be politically correct.

As a result, St-Pierre spends his days speaking in clichés, being careful not to annoy. He's pleasingly pleasant but desperately tries to avoid anything even remotely offensive.

With Diaz, though, it's vastly different. Despite his rambling and occasionally bizarre answers, Diaz came across during the conference call more real and likable than St-Pierre.

St-Pierre has become so sanitized that he's like an automaton, spewing his pre-programmed lines.

Diaz is as real as a kick to the face – blunt, honest and direct. You may not like his answers, but there is little doubt he's speaking from his heart.

Ronda Rousey, the UFC's bantamweight champion, trained with him and found him to be vastly different than the public's perception.

"He's a sweetheart," she said. "Nick is just a really, really shy guy. He's not a punk or a guy who is nuts, but doing interviews, that makes him anxious. It causes him anxiety and if something causes you anxiety, you're going to avoid it. I think that's why he avoids the media. Because of that, sometimes things don't come out right and if things don't come out right, it makes him more anxious.

"It's a vicious cycle like that. It's not his soul; it's not who he is. He's a really sweet guy and he's so dedicated to being the best he can be. But he's not comfortable [being interviewed] and it kind of sometimes gets out of control."

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Diaz, 29, has been a professional for 11 years and has been one of the best in the world for probably 10 of them. He's 26-8 with a no contest and has won 11 of his last 12 fights and 15 of his last 17.

He's held the Strikeforce title and has beaten a slew of elite fighters, but he's dwarfed by the massive shadow cast by St-Pierre.

Diaz clearly doesn't get the marketing aspect of it that St-Pierre long ago grasped. Diaz has always believed that respect and recognition and public adoration would come as a result of hard work in the gym and performing well in the cage.

That's a part of it – a small part – but presenting a wholesome image is just as significant.

"I don't get a lot of recognition for what I'm doing here," Diaz said.

Later, he added, "Nobody knows who I am. Well, I mean I guess everybody does, but as far as your mainstream magazines and, you know, [corporate sponsors like] Nike, adidas, all that good stuff, you know, I'm left out of that."

The commercial promoting the event repeats a line that UFC president Dana White spoke at UFC 137 after Diaz had routed B.J. Penn in 2011. Quoting St-Pierre, White said, "He's the most disrespectful human being I've ever met."

That hasn't escaped Diaz's notice. Diaz desperately craves public respect, to be regarded the way St-Pierre has been and to have sponsors willing to pay him to wear their logos.

In many ways, it is St-Pierre who is the phony. He has said repeatedly how much he hates doing media, but he uses every media opportunity to reinforce the carefully crafted image of himself.

During the conference call, St-Pierre admitted that though he has a Twitter account, he has never tweeted. He has assistants do that for him, he said.

Diaz can't afford assistants to tweet for him, though he clearly wishes he could.

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"Georges, they got somebody over there powdering his nose up, you know, and they're going to send him off for a video shoot," Diaz said. "You know, he's got someone who will [do his] Twitter for him. Now, he don't know how to talk, he don't know how to act right. He's got people living his life for him in the open or in the public, I mean that's … I don't know how, I would like to just stay out the place. I would like to just keep it real, you know. That way, I don't have to put out no image. I don't know how that works."

The UFC has trademarked the slogan, "As real as it gets," and there is little doubt that Diaz is 100-percent real.

Those who appreciate brutal, unfiltered honesty can identify with Diaz.

But as Col. Nathan R. Jessup, Jack Nicholson's character in the classic 1992 film, "A Few Good Men," might have said, most people can't handle the truth.

The public prefers a polished diamond to an unvarnished rock. And it's up to Nick Diaz to come to terms with that.

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