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Junior Dos Santos stopped Cain Velasquez just 1:04 into their UFC heavyweight title bout Saturday night, claiming Velasquez's belt and bringing a swift end to the mixed martial arts promotion's prime-time network debut.

Dos Santos hit Velasquez with an overhand right early in the first round, staggering the previously unbeaten champion to the canvas. The Brazilian challenger jumped onto Velasquez, who defended himself briefly before finally succumbing to Dos Santos' relentless ground-and-pound blows.

The brief fight was the only event on a one-hour broadcast on Fox, which signed the UFC to a seven-year broadcast deal earlier this year.

"I have no words to say what I'm feeling," said Dos Santos (14-1), who burst into tears in celebration. "It's amazing, my life. I have a lot of good people around me. I think Cain Velasquez was for sure my toughest opponent. I was afraid to fight with him, because he's very tough. I was not 100 percent for this fight, so I was scared."

Nobody could tell -- certainly not Velasquez, whose yearlong reign ended in his first title defense.

"I just want to say sorry to all my fans, family and friends. I disappointed you," Velasquez said. "I'm much more than this. I will be back, and I will get that belt back."

Velasquez (9-1) said Dos Santos' only big punch disrupted his equilibrium when it landed behind his ear. The first minute before Dos Santos' decisive blow included almost no action except a takedown attempt by Velasquez that was thwarted by Dos Santos.

"It was a good shot," Velasquez said. "He has a lot of power. I waited too much for him. He went in and did what he was supposed to do, so my hat is off to him."

The national television audience got a taste of MMA's violence, but not much else in the incredibly short fight. UFC President Dana White chose these two fearsome fighters for his Fox debut because of the high potential for a stoppage victory -- but White wasn't thrilled with just how quickly that stoppage arrived, criticizing Velasquez's decision to stand and fight with Dos Santos, one of the best boxers in MMA.

Velasquez hadn't fought since October 2010, when he claimed the belt from Brock Lesnar in the same octagon at Honda Center. After recovering from surgery on his torn rotator cuff, Velasquez knew he had a tough comeback fight against Dos Santos, the preternaturally strong fighter who had won eight straight bouts.

Dos Santos earned the title shot with a victory over Shane Carwin in Vancouver in June. His next opponent is expected to be the winner of Lesnar's bout against Alistair Overeem in Las Vegas on Dec. 30.

Dos Santos becomes the UFC's third Brazilian champion, joining featherweight belt-holder Jose Aldo and longtime middleweight champ Anderson Silva, widely considered the world's top pound-for-pound fighter.

Dos Santos has been a menacing prospect on the UFC horizon for several years, and he introduced himself to more casual MMA fans by serving as a coach opposite Lesnar on "The Ultimate Fighter," the UFC's popular reality show, earlier this year.

Like Velasquez, Dos Santos took up MMA relatively late, turning pro at 21 in 2006. He received his only professional loss in November 2007 when Joaquim Ferreira submitted him in the first round, but Dos Santos has rarely even been in trouble in a fight since.

Dos Santos made a spectacular UFC debut in October 2008, stopping heavily favored Brazilian Fabricio Werdum just 1:20 into the first round of their bout. He climbed the heavyweight ladder with stoppages of veterans Stefan Struve, Mirko "Cro Cop" Filipovic and Gabriel Gonzaga before winning decisions over Roy Nelson and Carwin.

Exactly 18 years to the day after the UFC debuted with an eight-man tournament featuring no weight classes and one-round fights to the finish with almost no rules, MMA's dominant promotional company kicked off its long-anticipated major television contract with its first live prime-time show. Most of the broadcast was taken up by a primer on MMA and the two fighters -- along with more post-fight analysis than expected.

Velasquez and Dos Santos both had ended nearly all of their fights by early stoppage. Velasquez was a star wrestler at Arizona State, while Dos Santos is fluent in Brazilian jiu-jitsu. They are the top two young heavyweights in MMA, quietly building toward this bout while Lesnar, the former pro wrestler, gets much of the casual fans' attention.

Benson Henderson won A unanimous decision over Clay Guida in the final undercard fight at Honda Center, which has hosted several major MMA events in the sport's relatively short history.