UFC 137: Penn vs. Diaz
UFC 137: Penn vs. Diaz was a mixed martial arts event held by the Ultimate Fighting Championship on October 29, 2011 at Mandalay Bay Events Center in Las Vegas, Nevada.
- Seánra:
- Stiúideo: Zuffa
- Eochairfhocal:
- Caitheadh: Nick Diaz, B.J. Penn, Cheick Kongo, Matt Mitrione, Roy Nelson, Mirko Filipović