Who doesn’t love an underdog? A Rocky in the ring? With the audience for boxing eroding, the new ring is an octagonal cage. In popularity and profits, mixed martial arts, or MMA, has knocked out boxing in the past decade. The Ultimate Fighting Championship, MMA’s flagship event, was sold for two million dollars in 2001. Today, it’s worth an estimated one billion. Our guest today is a definitive UFC underdog. He’s a writer who dove George Plimpton-style into the grueling world of MMA and landed in the octagon.