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.

The former Strikeforce champion, who infamously cost himself a title shot with Georges St-Pierre when he skipped pre-event media commitments, instead took out his frustrations on B.J. Penn and battered the former UFC champ into the night's second career retirement. Both fighters showed impressive striking accuracy in the first round, one in which Penn took Diaz's back but couldn't capitalize once on the mat. But on the feet, he matched Diaz's punches and landed the type of accurate blows the former Strikeforce champ has rarely dealt with in recent fights. In the second, Penn again was willing to stand flatfooted in the pocket, and especially in the clinch, he did damage with punches. But Diaz returned fire with some body shots and knees to the head while Penn was backed against the cage. The exchanges built Diaz's confidence, and with his first true taste of blood, he teed off with more frequency and dug into Penn's ribs with body shots. Subsequent combinations put Penn in survival mode, and the former two-division champ took heavy damage in surviving the final minutes of what proved to be a disastrous round for him. Despite the lopsided second round, Penn was willing to play Diaz's game in the third. He got sucked into the streetfight and had his moments, but Diaz's stellar conditioning and avalanche of punches simply proved too much to overcome. The fighters closed out the round by dishing out a ridiculous amount of damaging punches, but Penn, who was badly bloodied and bruised in the fight, couldn't get the finish he needed for the victory.

In the end, the judges scored it 29-28, 29-27 and 29-28 in Diaz's favor.

After the fight, a seemingly dejected B.J. Penn said his illustrious career is over.

UFC 137: Penn vs. Diaz Results:

Preliminary card (Facebook)

Middleweight bout: United States Dustin Jacoby vs. United States Clifford Starks – Starks defeated Jacoby via unanimous decision (30–27, 30–27, 30–27).

Middleweight bout: United States Chris Camozzi vs. France Francis Carmont – Carmont defeated Camozzi via unanimous decision (30–26, 30–27, 30–27).

Lightweight bout: United States Ramsey Nijem vs. United States Danny Downes – Nijem defeated Downes via unanimous decision (30–25, 30–26, 30–27).

Light Heavyweight bout: United States Brandon Vera vs. United States Eliot Marshall – Vera defeated Marshall via unanimous decision (29–28, 29–28, 29–28). This bout aired on the Spike broadcast following the Siver vs. Cerrone fight.

 

Preliminary card (televised)

Catchweight (148 lb) bout: United States Tyson Griffin vs. Poland Bart Palaszewski – Palaszewski defeated Griffin via KO (punches) at 2:45 of round 1.

Lightweight Bout: Germany Dennis Siver vs. United States Donald Cerrone – Cerrone defeated Siver via submission (rear naked choke) at 2:22 of round 1. This bout aired last on the PPV broadcast following the Penn vs. Diaz fight.

 

Main card

Featherweight bout: Japan Hatsu Hioki vs. United States George Roop – Hioki defeated Roop via split decision (29–28, 28–29, 29–28).

Bantamweight bout: United States Scott Jorgensen vs. United States Jeff Curran – Jorgensen defeated Curran via unanimous decision (29–28, 29–28, 30–27).

Heavyweight bout: Croatia Mirko Filipovic vs. United States Roy Nelson – Nelson defeated Filipovi? via TKO (punches) at 1:30 of round 3.

Heavyweight bout: France Cheick Kongo vs. United States Matt Mitrione – Kongo defeated Mitrione via unanimous decision (30–27, 30–28, 29–28).

Welterweight bout: United States BJ Penn vs. United States Nick Diaz – Diaz defeated Penn via unanimous decision (29–28, 29–27, 29–28).

  

The Ultimate Fighter 10 Finale

December 5, 2009

The Palms Casino Resort in Las Vegas, Nevada

 

Main Bouts

Roy “Big Country” Nelson vs. Brendan “The Hybrid” Schaub – The Ultimate Fighter 10 Finals

   – Roy Nelson stops Brendan Schaub by knockout at 3:45 of the first round. Roy Nelson is crowned the winner of season 10 of The Ultimate Fighter.

Matt “The Hammer” Hamill vs. Jon “Bones” Jones

   – Jon Jones is disqualified for an illegal strike at 4:14 of the first round. Jones delivered a “12-to-6″ vertical elbow that split open the bridge of Hamill’s nose. Whether or not Hamill could have continued is debatable. An official time was not given.

Houston “The Assassin” Alexander vs. Kevin “Kimbo Slice” Ferguson

   – Kimbo Slice defeats Houston Alexander by unanimous decision (29-28, 29-28, 30-27)

Marcus “Big Baby” Jones vs. Matt Mitrione

   – Matt Mitrione stops Marcus Jones by knockout at the :20 (Punches) mark of round two.

Frankie “The Answer” Edgar vs. Matt Veach

   – Frankie Edgar stops Matt Veach by submission (rear naked choke) at 2:22 of round two.

 

Preliminary Bouts:

Mark Bocek vs. Joe Brammer

   – Bocek defeated Brammer via submission (rear-naked choke) at 3:36 of round one. This bout aired on the Spike broadcast after the Slice vs. Alexander fight 

Dennis Hallman vs. John Howard

   – Howard defeated Hallman via KO (Strikes) at 4:55 of round 3

Brian Stann vs. Rodney Wallace

   – Stann defeated Wallace via unanimous decision. (30-27, 29-28, 29-28)

Jon Madsen vs. Justin Wren

   – Madsen defeated Wren via split decision. (30-27, 28-29, 29-28)

James McSweeney vs. Darrill Schoonover

   – McSweeney defeated Schoonover via TKO (Strikes) at 3:20 of Round 3. This bout aired on the Spike broadcast after the Jones vs. Hamill fight