Junior dos Santos dropped Cain Velasquez with a right behind the ear and finished him with 12 shots on the ground to win the UFC heavyweight championship.
Dos Santos, a 27-year-old fighter (14-1) from Salvador, Brazil, grew up with a mother who earned $200 a month in the city that was a hotbed for an early version of the sport 50 years ago. And dos Santos captured the title on what was arguably the most important show the company has produced.
"I have no words to say what I'm feeling," a teary-eyed dos Santos said. "It's amazing, my life. I want to thank all of my team, all my family, I've got a lot of good people around me. Thank you very much."
Dos Santos was booed heavily by the pro-Velasquez crowd at the Honda Center, the same arena in which Velasquez (9-1) won the title on Oct. 23, 2010, from Brock Lesnar.
The bout was arguably the highest-level heavyweight title fight in the sport's history, as it matched two fighters who had never faced serious adversity in their UFC careers.
[ Related: Henderson defeats Guida in thrilling fight ]
Velasquez, a 7-to-4 favorite going in, had not fought since winning the title due to surgery for a torn rotator cuff in his right shoulder.
The show was hoped to be Velasquez's coming-out party before a network TV audience in an attempt to establish him as a superstar to the Latin American community.
"I'm sorry for all the fans, my family and my friends that I disappointed you," Velasquez said. "I will come back. I will get this belt back for sure."
Dos Santos will next face the winner of a Dec. 30 fight between Alistair Overeem and Lesnar in Las Vegas.
While the main event didn't turn out to be the struggle of a lifetime, the semifinal bout, which didn't air on Fox, more than made up for it to the live crowd. In a battle for a lightweight title shot, Ben Henderson (15-2) won a unanimous decision over Clay Guida (29-12) by scores of 30-27, 30-27 and 29-28.
The crowd gave both men standing ovations after all three rounds in a fight that will be under consideration for "Fight of the Year" honors. But Henderson just had too much skill for the relentless Guida, who recovered from two immediate knockdowns in the first round and had Henderson in trouble on a few occasions with a guillotine choke.
Henderson will face champion Frankie Edgar, tentatively scheduled for Feb. 26 in Saitama, Japan.
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- Cain Velasquez
- Junior dos Santos