When the International Fight League invited me to legend Renzo Gracie's Manhattan studio to train with the New York Pitbulls, I felt as if I were being called up from the minors.

No sweat. I live mixed martial arts. I've studied Gracie jiu jitsu for five years, wrestled in high school, kickboxed in junior high. Here was a chance to train with the second-seeded Pitbulls for their semifinal matchup Thursday night against the Tokyo Sabres at the Meadowlands. The Los Angeles Anacondas face the Quad Cities Silverbacks in the other semifinal at the Meadowlands on the same night, with the championship match on Sept. 20 at the Hard Rock Hotel and Casino in Hollywood, Fla.

The International Fight League did not ask me whether I had trained in mixed martial arts, which is a hybrid of boxing, wrestling, kickboxing and submissions grappling. I assumed that the IFL representative thought I would be a geek journalist in awe of MMA because I'm a fan. Instead, they got a 6-foot-2, 240-pound fighter of African American, Irish and Choctaw heritage.

From the street outside the studio on West 30th Street last week, there were no signs to even hint that people were straining to escape choke holds in the basement.

Inside, two or three fighters recognized me from previous grappling competitions. One stood out, but I was unsure because he looked like a longer, hairier version of someone I once knew.

"Hey, brah, what's your name?"

"Rhalan."

"It's me, man, Kéi!"

When I last saw Rhalan Gracie, son of Master Relson Gracie, he was a 15-year-old in Oahu, Hawaii.

Now, I was exposed. I was a fighter posing as a journalist.

By the time Renzo Gracie arrived, we had warmed up. With each technique, we added more protective gear - mouthpieces, shin guards, gloves.

Renzo designated a 260-pound sparring partner for me and instructed him not to take it easy. We felt each other out at first, checked for striking distance, speed and strength.

My T-shirt got drenched with sweat. When I finally took the head gear off and felt the urge to vomit, I dared not. My body wanted to call it quits, but my heart said no.

We moved on to training for ground work, grappling, jiu jitsu. I was in my element, and my new sparring partner was much smaller, but equally skilled.

After about 20 minutes of that, I got to practice with a heavier opponent. It was Bryan Vetell, a 6-1, 290-pound heavyweight. His build resembled a hybrid of a rhino and a miniature Hulk.

At one point, he took a deep breath and explosively sent me into the air. I felt like a fish floundering at the bottom of a boat.

Vetell was focused, skillful and powerful. After a while, I could tell that he was letting me get the top position, training to keep himself on the bottom. I had trouble with his explosiveness.

Finally, the training session was over after two hours of hard-core MMA. I was shaking with adrenaline, but had a much better understanding of why a team concept works for individuals.

Renzo explained: "You know, I always saw this sport as an individual sport, but I never realized I was always part of a team, Team Gracie, my brothers and my cousins. Training is easier with a team. The team format definitely makes a better fighter, your team pushes you forward, everybody on the same page, same direction."

He said that the moment you want to relax a little, the team pushes you to work harder.

Quitting wasn't an option. It reminded me of my Marine Corps days.

The next day, Vetell asked me how I felt.

"Sore, very sore," I said.

"You get used to it," he said.

Tomorrow night, the fight spectators will see why being sore is worth it.

If you go: International Fight League 2007 Championship Semifinals, 7:30 p.m., Meadowlands, East Rutherford, N.J., against the Tokyo Sabres ($40-$175, www.ifl.tv or www.ticketmaster.com)