And in Saturday's UFC 137 main event, all the fight talk seems to center around the participants' boxing. For years, BJ Penn has been considered to have some of the best hands in MMA. And his opponent Nick Diaz recently made waves after nearly turning his back on the sport to try his hands in the squared circle. Given their pedigrees, contrasting styles and differing body types, the standup figures to produce compelling, unpredictable action.
Even to the learned eye of Penn's boxing coach Jason Parillo, who was undefeated in an eight-fight pro boxing career, it's a hard one to analyze. As Parillo noted in an interview with MMA Fighting, the many options a fighter has at his disposal make it hard to determine how a fight will develop.
"You've got a guy who loves to box and wants to fight Roy Jones, Jr, and you've got another guy who's been recognized as one of the best boxers in the MMA game," he said. "You've got two high-voltage submission guys. Realistically, I think Nick's going to try to keep BJ in a boxing match. I believe he feels he's got something to prove with his boxing ability. He loves boxing and I think he wants to prove something using BJ to show he's the best boxer in the MMA game. This fight can go anywhere. It really can. It's tough to predict MMA fights in general, but this one can go in so many ways."
On their feet, their styles are very different. Penn relies on speed, accuracy and power with crisp combinations. But the rangy Diaz uses his length and non-stop volume to keep opponents at distance and to set up his occasional power strikes.
Given the way their styles and bodies match up (Diaz has a four-inch reach advantage), Penn said getting inside might prove to be the biggest challenge for him.
"That's huge, that's huge," he told MMA Fighting. "You've got to get in on Nick Diaz. He's got that reach, and not only does he have that reach, he knows how to put you in the perfect spot. He's not really a big footwork guy but if you come forward he'll take one step back and just keep you on the end the whole time. We're going to have to -- without giving anything away -- use a lot of smarts and technique to get in there, get after him and attack him."
Penn made some headlines recently when he called Diaz the best boxer in MMA. Diaz was flattered to hear the comments but believes he might have put in more time training with high-level boxers than anyone in the UFC.
And regardless of the compliment, Diaz isn't letting it go to his head.
"This is MMA too, so regardless of how you win a fight, whether standup, winning on punches, I don't think it has anything to do with boxing," he said. "Just throwing more martial arts in than boxing, when it's MMA, everything changes. Stance is different, you have to defend the takedown, you have to defend the leg kick. You can't really say or judge."
That's true, of course. If a fighter gets too reliant on his hands and having success with it, his opponent can always change levels and go for the takedown. Penn has that in his arsenal, though it's a weapon he only occasionally decides to use. In his last five fights, he has four takedowns in just six tries. But for Diaz, it's not his strongest weapon. In his last five fights, he has completed just two takedowns in 10 tries.
Given their usual reluctance to use wrestling, it's not a stretch to think that collectively, the two might shun it altogether and decide things on their feet. So will Diaz's constant activity and volume overwhelm Penn, or will the former two-division champion find a way to get inside of his opponent?
"Nick's got a lot of confidence to use that style," Parillo said. "He's not the most devastating, heavy puncher, but he knows how to set up the big shot, for sure. And he understands boxing. BJ's got speed, and he's cleaner and sharper. I feel the fire more from him than I have in the last couple fights. He wants to show he can beat guys at the top tier. If he makes a decision to be there and has the hunger to win, he's going to do it."