Rugged fighter B.J. Penn has held UFC's lightweight crown for nearly eight years but meets a ferocious challenger in Diego Sanchez, who faces Penn in the Octagon in a bout filmed live in Memphis, Tenn. The mixed martial arts extravaganza includes a fierce match between Frank Mir, hunting for his third UFC title, and Cheick Kongo, seeking his first title. Also fighting are heavyweights Paul Buentello and Stefan Struve.