Matt Mitrione was cut by the Vikings in the middle of the 2005 season after being inactive on game day for several weeks in a row. He went from being an NFL defensive lineman one week to a dad in need of a paycheck the next when his son was born shortly thereafter.

"I went to work in corporate America," Mitrione said. "I designed benefits packages and sold them to companies."

Quite a switch. How'd that go?

"It was a great job, but I'm more of a competitive athlete," Mitrione said. "I don't get my jones from paperwork."

That realization, along with some auspicious opportunities and connections along the way, led Mitrione into the world of mixed martial arts. On Sunday, the heavyweight -- who was previously a cast member on the Spike TV show "The Ultimate Fighter" -- will battle Christian Morecraft in a three-round televised bout starting at 8 p.m. on Versus.

Mitrione, 32, who trains in Indianapolis, was introduced to MMA in part through friend and fellow athlete Jayson Werth, a veteran MLB outfielder. Werth put together an amateur MMA event several years ago and asked Mitrione to compete. He agreed, and while an injury during training prevented him from fighting in that event, it sent him on his way to a competitive transition from football.

Mitrione played in college at Purdue and was with the Giants before his two stints with the Vikings -- the first in 2005 and the second, more briefly, during a post-draft camp in 2008. The raw aggression would seem to transfer over well, but Mitrione -- listed at 300 pounds during his NFL days and 275 now -- says there are relatively few ex-football players now trying their luck with mixed martial arts.

"I wish there were more, to be honest," Mitrione said. "I'm still a football player at heart who competes in MMA. I played football for 19 years. ... Football gave me self-discipline, motivation and heart. I'm too stubborn to quit. I feel that I learned through NFL camps. Someone is always trying to take your job."

As a result, he has what he hopes is a budding new career. Mitrione is 4-0 as a professional. His new goals are squarely focused on MMA, not the NFL.

"I'm done with football, and football is done with me. There are no dreams left there," he said. "MMA is good to me. I enjoy the grind and the learning process. Even if I get my [butt] kicked, I'm still going to have a great time doing it."