TORONTO - It's welterweight champion Georges St-Pierre's well-stocked arsenal against challenger Jake Shields' prickly grappling.
St-Pierre (21-2) has won his last eight fights and has not lost a round since August 2007 -- a string of 30 straight. Shields (26-4-1) is riding a 15-fight win streak dating back to 2005.
Something has to give Saturday night at UFC 129, before a record North American MMA crowd of 55,000 at the Rogers Centre.
St-Pierre is fighting for his legacy. A win over Shields and the 29-year-old from Montreal has all but cleared out the 170-pound division.
Shields is battling for respect. A multiple champion in other organizations, the 32-year-old California fighter is a latecomer to the UFC and as such has missed out on much of the spotlight.
Some bookies see St-Pierre as a overwhelming favourite, odds that the champion ridicules. He calls Shields his greatest threat.
It's a line GSP has used before but he sounds like he means it this time. And others agree.
"if there's anybody out there that can give GSP a good fight, I think Jake Shields might be the man," said former lightweight and welterweight champion B.J. Penn, beaten twice by St-Pierre.
"When you look at him, you don't think much. You see him fight, you don't think much but he goes out there and wins. He beat (middleweight) Dan Henderson, I know it's a different style and styles make fights but I think Dan Henderson would do really well with GSP if they were in the ring together. I honestly think it's a toss-up."
English welterweight Paul (Semtex) Daley also was impressed by Shields' win over Henderson in Strikeforce.
"Dan Henderson's no joke so I think that just goes to shows the sort of calibre of fighter Jake Shields is," said Daley. "That being said, Jake Shields is slightly more one-dimensional than Georges St-Pierre and if Georges St-Pierre can keep the fight standing then I think Georges St-Pierre has a high chance of winning the fight.
"And I don't doubt that Georges St-Pierre is going to come and try and take Jake down as well and try and do some damage from top position. But I think we could be in for an upset. Jake Shields is very capable and good at what he does."
Unlike St-Pierre, Shields has also fought at 185 pounds. But expect St-Pierre to be the bigger man when they meet in the cage Saturday.
The GSP camp expects the champion to weigh a little over 190.
"Jake Shields was a little bigger than him so we put on a little more muscle with Georges," said coach Firas Zahabi. "He's been doing a little more Olympic (weight) lifting.
"We've increased his volume there to make sure he's the bigger guy or at least that Jake doesn't have the advantage there, that they're equal size."
Shields did not get his weight cut right last time out, in his UFC debut against Martin (The Hitman) Kampmann last October, and had to lose 20 pounds in 24 hours.
He expects to be 183 fight night.
"I'm a lot lighter than I have been in the past," he said. "I had a huge weight cut last time, walked to the cage at 190 and I felt like instead of helping me, the extra weight hurt me ... I feel like conditioning is key for this fight so I decided to go a little bit lighter."
Whatever his weight, Shields is dangerous with his own brand of American jiu-jitsu -- he has his own patented logo which is tattooed on has right forearm.
A former wrestler who has a black belt in Brazilian jiu-jitsu under Cesar Gracie, Shields' style is a combination of both.
"My style is not really wrestling or Brazilian jiu-jitsu, so I kind of fused it," he explained.
It has served him well. Shields, who is tough and durable, has 10 submission wins in addition to his 13 decisions and three TKOs.
He has lost three decisions and been stopped by TKO once.
"He's been able to take down people who nobody thought could be controlled and finish them," said John Danaher, St-Pierre's BJJ guru.
Adding to the threat is the fact that Shields' weapon of choice is a guillotine choke which, as Danaher notes, "can be employed from almost any position -- top or bottom, standing or ground."
Danaher compares it to a knockout punch.
"It's a threat that can occur at any time in the match ... and that's what makes him such a dangerous opponent."
Danaher rates Shields as strong in both top and bottom position but notes almost all his of his finishes have come from the top position.
St-Pierre is also a BJJ black belt but, as he himself acknowledges, Shields is a black belt like few others.
The St-Pierre camp sees a lot of their fighter in Shields. The champion calls him "a thinking fighter.
"He always reinvents himself. He travels to train, he doesn't stay in his comfort zone. He's a very clever guy, That's why he's so dangerous."
St-Pierre, meanwhile, travelled to London to prepare for Shields, training with elite grapplers Roger Gracie and Braulio Estima.
Shield's split decision win over Kampmann is not representative. Which is good considering he converted just four of 15 takedown attempts and landed 25 significant strikes in three rounds, according to FightMetric.
Compare that to St-Pierre's last fight, when he used his piston-like jab (winning the striking battle 118-14 over five rounds) to destroy his opponent. Koscheck needed surgery after his face was busted up in the first round by the champion's jab.
St-Pierre was also good on four-of-nine takedown attempts.
"He's either going to keep him on the end of his jab for 25 minutes or it's going to be a hugfest on the floor," said English welterweight Dan (The Outlaw) Hardy, soundly beaten by St-Pierre at UFC 111. "But either way I think GSP's going to take it."
St-Pierre is all about taking his opponents where they don't want to go. For example, he took the striker Hardy down 11 times in their fight.
St-Pierre has been able to take opponents down at will -- in his last five fights he has been good on 34-of-46 takedown attempts compared to one-of-10 for his opponents.
And while he has stopped just one of those fighters -- Penn's corner threw in the towel after four rounds -- he has done damage with his fists.
The question is does St-Pierre want to take the fight to the ground when he has the edge standing? Chances are the champion will mix it up, looking to leave the challenger guessing.
For those who say Shields doesn't have the weapons that St-Pierre has, Zahabi has an answer.
"I won't say he's as well-rounded as Georges by any means, but he doesn't have to be," Zahabi said. "He's the best at jiu-jitsu, so if he brings you down into his realm he will beat you there."
Shields took his time getting to the UFC. But he picked up championship belts along the way in Strikeforce, EliteXC, Rumble on the Rock and Shooto.
While St-Pierre has been a consistent winner since regaining his title from Matt Serra at UFC 83 in April 2008. he has come in for some criticism that he has not finished his opponents. His fights have gone to a decision four of five times since then.
"I personally believe that Georges is if not the best pound-for-pound fighter, definitely one of the top two or three pound-for-pound fighters in the world," said Canadian middleweight Jason (The Athlete) MacDonald, who takes on Ryan Jensen on Saturday's card.
"And obviously there's a lot more at stake when Georges fights than when I fight. Georges, I find, has a tendency to fight very safely. And I understand that. He's a champion, we're talking millions and millions of dollars for him. But I think Georges has the ability to go out there and finish guys every fight, and sometimes I find it frustrating and disappointing that he doesn't do that, that he doesn't take more risks and go out and do that.
"That being said,I understand why he doesn't do that. But for me, I'd like to think if I had Georges' talent or even half of it, I'd be out there finishing every fight."
Zahabi says being a champion means having a target on your back. Everyone is up for the challenge.
"You know I don't believe Georges plays it safe," he said. "I think he plays it to finish, but it's hard to finish a guy who is preparing for a world title fight.
"Not to make excuses but he's just fighting his opponents at their best all the time. (Middleweight champion) Anderson Silva's had trouble finishing and then the next few fights he would finish his opponents in dramatic fashion.
"Let's see what happens this Saturday."
St-Pierre, for one, says nobody will nod off during the main event.
"It's going to be a good fight, maybe one of the best fights of the year," he said.
"Believe me, nobody's going to boo," he added. "Either on the ground or standing up, there's going to be a lot of action. The real mixed martial arts fan that comes to see a real mixed martial arts fight, they will appreciate the show."
Featherweight Mark (The Machine) Hominick of Thamesford, Ont., takes on 145-pound champion Jose Aldo in the co-main event. The dangerous Brazilian, whose UFC debut has been delayed by injury, is a heavy favourite.
Hominick is one of 10 Canadians on the 12-fight card.
Also on the main card, former heavyweight and light-heavyweight champion Randy (The Natural) Couture walks into the cage for the last time, to tackle former light-heavyweight title-holder Lyoto (The Dragon) Machida.
At age 47, Couture is giving up 15 years to Machida.