NEW YORK— “The American Gangster” is hanging up the gloves following Friday night’s Bellator 222 event at Madison Square Garden.

In a heartfelt, and at times emotional, post-fight news conference Chael Sonnen detailed his decision to walk away from the sport of mixed martial arts. Sonnen said the retirement was not predetermined before the fight but felt right given the way things played out.

“No, I didn’t have that planned,” Sonnen said. “I thought I was going to win this fight and call out Ryan Bader. Everything was going my way until it wasn’t. But no, I don’t regret it. It was a No. 1 contender’s match, and I thought it was a big opportunity, and it was. It’s somebody else’s turn.”

While his retirement wasn’t decided before entering the cage, Sonnen came to a realization once he stepped inside. Taking on Machida, he felt he was lacking the intangible tools that made him a successful fighter.

“You’ve got to be tough in this sport,” Sonnen said. “I feel like I used all of my toughness up. There was some positions in there that, before in my career, I would have walked right through them. I did mind losing to him in his spots – you know, some of the stuff on our feet and those jumping knees and whatnot. But I did mind losing to him in my spots. He was on top of me, and I didn’t think he’d be on top of me.

“I thought I could have scrambled. I thought I could have gotten up. I used to be tougher. I used to want it more. I used to have more grit, and I just felt like maybe I fired my last bullet. I didn’t have that same grit, and it’s time to move on.”

Sonnen, 42, finishes out his Bellator MMA tenure with a 2-3 record, with wins over Wanderlei Silva and Quinton Jackson. His losses were suffered at the hands of Tito Ortiz, Fedor Emelianenko, and Machida.

He ends his 22-year MMA career with a 30-17-1 record, contending for the UFC title on three different occasions.

For complete coverage of Bellator 222, check out the MMA Rumors section of the site.