Georges St-Pierre speaks to media following his welterweight title fight...

Georges St-Pierre speaks to media following his welterweight title fight against Nick Diaz at UFC 158 in Montreal. St-Pierre won the match by unanimous decision. (March 16, 2013) Credit: AP

Georges St-Pierre may never again move barefoot around the UFC's octagon as thousands of people in the arena chant his name.

No punch or kick chased the greatest welterweight champion in UFC history away from the cage. No diminished skill set, no slowness from age. Simply his own mental obsessions.

"Mentally, I just feel like I can not go through another training camp right now and I don't know when I will be able to," St-Pierre said Friday, when he announced he is vacating his title and taking a break from MMA. "It's like every fight, I'm carrying weight on my shoulders. And, every fight, it's like you add weight on your shoulders. Every fight, you add weight, you add weight and you add weight. At one point, it becomes so heavy, I have a hard time carrying it myself."

Very few athletes, let alone fighters, leave on their own accord. More often, someone else makes that decision for them. An opponent, a general manager, an owner.

In this case, St-Pierre chose. He gave up the one thing that always drove him to push his body to the limit -- the championship belt. That 15-pound strap of gold that signifies there's no one better.

St-Pierre (25-2) has the most wins in UFC history with 19. His run of nine straight title defenses is second best in UFC history. We throw the word "great" out too much in sports, but with St-Pierre, it's not enough. He dominated opponents, one after the other, for more than five straight years -- and that's after he won the title a second time.

"He's the greatest welterweight ever," UFC president Dana White said. "He's the gold standard for everything.''

So there sat St-Pierre in a mall in Quebec, telling reporters on a conference call that he no longer could handle it all.

This wasn't the same GSP who could own a press event with his French-Canadian accent, professionalism and genuine charm. That was obvious from the tone of St-Pierre's voice for much of the call -- a combination of tension, stress, anxiety and emotion.

Instead, here was a 32-year-old -- a man who made a name for himself by being nearly invincible in physical combat with other men -- willingly walking down from atop the mountain.

St-Pierre said he has personal issues to tend to, same as he said last month after UFC 167, when he first mentioned taking a break. "My life, it's a freaking zoo right now," St-Pierre said Friday.

He would not elaborate on the issues that are plaguing him, which is perfectly fair. If they are enough to cause a true champion to give up what he dedicated his life to achieving, and to use terms such as "mental equilibrium" and "mental stability" so publicly and willingly, they must be significant.

"You can tell by the way he talks that the issues he's dealing with outside of the octagon are driving him nuts,'' White said. "He needs to button up some things in his personal life and then you'll see him again."

This was not a retirement -- officially. Perhaps leaving the door open makes it easier for people to digest the possibility of not seeing him fight again.

"I wanted to do things to be remembered, to make a difference in the sport, to make the sport reach a different level," St-Pierre said. "One day, when I feel like it, I might come back. But right now, I need a break."

Newsday LogoYour Island. Your Community. Your News.Digital AccessOnly 25¢for 5 months