Randy Couture, top, submitted boxer James Toney with a triangle...

Randy Couture, top, submitted boxer James Toney with a triangle choke in the first round at UFC 118 in Boston. (Aug. 28, 2010) Credit: AP

Randy Couture has waited long enough for the grand finale to his mixed martial arts career.

The 47-year-old MMA pioneer says he's finally finished with competition after taking on Lyoto Machida at UFC 129 in Toronto this weekend.

He plans go out in front of what's likely to be the biggest crowd in UFC history at the Rogers Centre, taking his famed cauliflower ears out of the octagon for the final time.

"It's been one that's been coming for a while," Couture said. "I realize I've pushed it a lot further than anybody is going to push it, and I just feel like I want to go out on my terms, and not after one or two or three losses and, you know, have everybody else telling you you should be retiring. I want to do it when I want to do it. I think now is the time."

The five-time UFC champion has defied age, occasional inactivity and numerous outside demands to remain a competent, dangerous fighter well into his 40s. He's also a successful actor, businessman and MMA trainer with no shortage of job offers outside the cage.

Although the relationship has been tempestuous, Couture has been inextricably linked with the UFC since 1997, when he fought at UFC 13 in a four-man heavyweight tournament shortly after picking up the nascent sport. He fought in Japan before reconnecting with the UFC in 2001, and became one of the promotion's brightest stars throughout MMA's evolution from an outlawed sport to a billion-dollar enterprise.

Couture stayed competitive into middle age with strict conditioning and discipline, even while on far-flung movie sets. His workouts are the stuff of MMA legend, and the former Oklahoma State wrestler only amped up his regimen in recent years.

"One of the things that I struggled with is that I am healthy as ever," Couture said. "I feel great. I absolutely have the ability to continue to compete, and compete at this level. I don't want to wait until I have those issues to think about."

Nobody ever knows for sure whether a fighter is truly finished, no matter what he might say leading up to a bout -- and Couture has tried to quit before.

He retired after losing his rubber match against Chuck Liddell in February 2006 to conclude one of the UFC's most memorable trilogies. After scrapping that plan and returning to win the heavyweight title, he walked away from the UFC again in a contract dispute in October 2007, only returning to the promotion a year later.

UFC president Dana White is among those who think Couture (19-10) might still have his competitive fire, and Couture hasn't dampened that fire by speculating about possible conditions under which he would fight again.

Yet there's ample reason to believe The Natural is serious about ending one of his sport's most remarkable careers. Couture has won three straight fights, and nobody doubts his ability to keep entertaining his rabid fans if he chose.

"I think it's time to focus on the other things I've got going on in my life after this fight," Couture said.

Although he has spent plenty of time every year working on movies, including last year's Sylvester Stallone hit "The Expendables," Couture has maintained for years that he had no timetable in mind for finishing his career. He accepted fights that intrigued him, most recently putting a beating on boxer James Toney last summer in Boston.

"They offered me a couple of other guys, and I turned them down," said Couture, who turns 48 in June. "I've watched Lyoto for a couple of years now, and I'm very appreciative of the way he competes. He just has such a unique style as an athlete, and I like that. Those are the kinds of fights that are intriguing and interesting to me, for me to try and figure out and protect myself."

This is no farewell appearance for a past-his-prime athlete: Couture picked a brutal challenge for his farewell. Although the 32-year-old Machida (16-2) has lost his last two fights, the former UFC light heavyweight champion's karate-based style has baffled most of his opponents.

"I had a great camp. Everything is spot-on," Couture said. "I've had to learn some new things, and he certainly has a complex and unique style. It's been fun to study that, and try and figure out what I think will work, and how to get the job done. He's a tremendous fighter and a tremendous athlete, so hopefully our training camp has been on, and we've got the right answers."

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