Georges St-Pierre wants to teach Nick Diaz a lesson in UFC 158

If you've seen heavy-rotation television advertisement pushing UFC 158, you've no doubt had the soundbite seared into your brain by this point: "You have no

Georges St.-Pierre (left) will be seeking his eighth straight successful title defense in UFC 158 :: /Getty Images

If you've seen heavy-rotation television advertisement pushing UFC 158, you've no doubt had the soundbite seared into your brain by this point: "You have no idea how dark I am in my head sometimes."

Those words come from one of the top pound-for-pound mixed martial artists on the planet, Georges St-Pierre, holder of the UFC welterweight title, winner of 10 straight fights and 16 out 17 going back to 2004.

It's a curious quotation from a fighter who's regarded as close to milquetoast as anyone can be in MMA's rough-and-tumble world. The Montreal native is known as one of the most polite, well-spoken personalities in the business, with the sort of squeaky-clean image that has attracted mainstream sponsors from Gatorade to UnderAmour.

So where does this "dark place" come from? Maybe it's the mental space the champion needs to inhabit to prepare to meet his alter ego on March 23 at Montreal's Bell Centre, Nick Diaz, a brawling, trash-talking bad boy from Stockton, Calif.

Maybe, now that he's a millionaire many times over and one of Canada's most popular athletes, it's simply the place he visits in order to summon the same fire he had when he was up-and-coming and hungry.

Whatever the motivation, St-Pierre insists it's real. "I know it might be hard to believe if you don't know me personally," the champion said last week in a one-on-one phone interview with Sports Illustrated. "But people around me, people who know me, ask them, they know. The thing is, maybe now I've achieved some success, maybe I can afford some things I couldn't before, but I went through a lot of bad times in my life, I had to overcome a lot of obstacles to get to where I am now.

"That's what keeps me going. That's where I go to find my motivation. That's the dark place, that is what gets me to the next level in my career."

St-Pierre prefers to keep the specifics of his "dark place" vague, but whatever they may be, they've found a target in Diaz. Their saga has played out over a nearly two-year span, as Diaz, the former Strikeforce welterweight champion, built up a 10-fight win streak.

But Diaz, a complex character who runs triathlons and touts the benefits of both organic eating and medical marijuana, has played the role of Goofus to the St-Pierre's Gallant over the years. Diaz was pulled from a planned 2011 title fight with St-Pierre after Diaz blew off a pair of press conferences. He was then suspended by the state of Nevada after testing positive for weed after a February 2012 loss to Carlos Condit, his second such test failure in that state.

In the leadup to this fight, Diaz was up to his old antics, as he repeatedly blew off the production crews for the "UFC Primetime" promotional vehicle, costing the company $50,000.

At this stage of the game, St-Pierre has simply grown tired of Diaz's antics.

"He's been disrespectful to me," St-Pierre said. "He's not the only fighter who's been disrespectful. Remember Josh Koscheck and B.J. Penn? Remember what they said? They were disrespectful. You saw how those fights turned out."

(For the uninitiated, St-Pierre dished out Penn such a beatdown at UFC 94 that Penn's corner threw in the towel after the fourth round, and Koscheck, after absorbing a five-round shellacking in December 2010, found himself on a surgeon's table a few days later, getting his busted orbital bone repaired).

The simple fact this bout was made, in and of itself, wasn't without controversy. This is Diaz's first fight since the suspension and the loss to Condit. Many feel 14-1 Johny Hendricks, who is fighting Condit in the co-feature bout at UFC 158, deserves the title shot. And moreover, the bout fits a pattern in which it seems the squeakiest wheel gets greased: Chael Sonnen is fighting for Jon Jones' light heavyweight title after Jones was called out, and Anthony Pettis, a top lightweight, is getting a shot at Jose Aldo's featherweight title simply because he asked for it.

"I'm fighting Nick Diaz because this is a fight that I want, and a fight that the fans want to see," said St-Pierre. "The sport is evolving, it's changing. The athletes who come into the sport in the future will be able to jump higher, run faster, hit harder than this generation did, just like we advanced over the generation before us. But the other aspect of the evolution is that you have to learn marketing. You have to learn the business aspect of the sport."

Few have mastered the business aspect of the the sport like St-Pierre. That, of course, leads to the inevitable question about the biggest business fight of all: A superfight. For all the bluster involved with the St-Pierre vs. Diaz fight, few aside from hardcore Diaz supporters see St-Pierre having much of a problem with Diaz. A GSP victory would be his eighth straight successful title defense and would assure he'd reach his fifth anniversary as champion, a mark surpassed only by current middleweight champion Anderson Silva.

St-Pierre's name has been linked to Silva for years, but talk in recent months, superfight chatter has shifted more toward Silva vs. Jones. More recently, lightweight champion Ben Henderson tried to call St-Pierre out for a superfight, which the latter summarily dismissed.

If the welterweight champ sees a superfight as a key to securing his legacy, though, he's playing it coy. It may even take him back to his dark place.

"My goal is to become the greatest mixed martial artist of all time," St-Pierre said. "That has been my goal since the first day I got into the sport and that hasn't changed. I've got a fight with Nick Diaz next week, and after that? I don't know. We'll have to wait and see. Ask me that again some other time."