UFC 137: “Penn vs. Diaz” event was held October 29, 2011 at the Mandalay Bay Events Center in Las Vegas, Nevada beginning at 6:15 p.m. ET. In addition to the pay-per-view event, UFC 137 also featured two-bout UFC prelims on Spike TV and an additional four fights which streamed live on Facebook.
Facebook.com Preliminary Fights:
Clifford Starks def. Dustin Jacoby via Unanimous Decision after 3 Rounds
Francis Carmont def. Chris Camozzi via Unanimous Decision after 3 Rounds
Ramsey Nijem def. Daniel Downes via Unanimous Decision after 3 Rounds
Brandon Vera def. Eliot Marshall via Unanimous Decision after 3 Rounds
Spike TV Preliminary Fights:
Bart Palaszewski def. Tyson Griffin via KO (punches) at 2:45 of Round 1
Donald Cerrone def. Dennis Siver via Submission (rear-naked choke) at 2:22 of Round 1
Pay-Per-View Fights:
Hatsu Hioki def. George Roop via Split Decision after 3 Rounds
Scott Jorgenson def. Jeff Curran via Unanimous Decision after 3 Rounds
Roy Nelson def. Mirko Filipovic via TKO (punches) at 1:30 of Round 1
Cheick Kongo def. Matt Mitrione via Unanimous Decision after 3 Rounds
Nick Diaz def. BJ Penn via Unanimous Decision after 3 Rounds