South Bronx resident Bradley Desir says fighting is nothing new -- he's being doing it for a living since 2005.

It's the type of fighting that's changed. The 30-year-old former Marine served in Iraq from 2007 to 2009.

"It was my job to blow in the doors," he says. "During fights, I would hit hard targets with rockets, like houses and cars, bunkers."

After returning from war and attending Fordham University, he says his interest in mixed martial arts blew up quickly.

"Everything in my life revolves around it," he says. "Everything else comes second after MMA."

He's got 14 professional fights under his belt.

"In combat, your fear is for your life, so, there's no fear of embarrassment," Desir says. "Fighting professionally, it's fear of embarrassment. That's what the fear is. I'm not scared to get hurt."

But despite the difference, he says a part of him returns to the desert every time he steps inside the cage.

"We call it violence of action," Desir explains. "Whatever you're gonna do, do it violently. I'm not all fire and brimstone like I was, but I don't really need to be. You could put anybody in front of me, and I'm gonna punch and kick until they fall or don't move."

His next fight, for Bellator Promotions and Spike TV's Veterans Operation Wellness program, is set for June 24 at Madison Square Garden.

"It's a life-changing opportunity," Desir says. "It's Madison Square Garden in New York City. It doesn't get any bigger than this."