Winning a UFC title is difficult; retaining it can often be even harder.
Heavyweight champion Cain Velasquez, a top-level wrestler, made the first defense of his title Saturday night in Anaheim, Calif., against the division's best boxer and top contender Junior dos Santos.
And the boxer won easily, knocking out Velasquez in the first round.
Dos Santos landed an overhand right that caught Velasquez on the left temple. The champion fell to the canvas and dos Santos swarmed him, landing several more punches before referee John McCarthy jumped in to stop the assault at the 1:04 mark.
The victory is a culmination of the hard work and determination that dos Santos has demonstrated throughout his life. He grew up in poverty in Brazil but always strived to improve his lot in life.
Becoming UFC heavyweight champion proved to all what hard work and determination can lead to.
"I have no words to say what I am feeling," an emotional dos Santos said after improving to 14-1. "It's amazing, my life. I have a lot of good people around me.
"Cain Velasquez was for sure my toughest opponent. I was scared to fight him because he is tough. I was not 100 percent for this fight."
Velasquez suffered the first loss of his professional mixed martial arts career. He fell to 9-1.
Despite the disappointment of losing his title, Velasquez warned that it would be a mistake to count him out in the future.
"I want to say sorry to all my fans, family and friends; I disappointed you," Velasquez said. "I will come back. And I will get this belt back, for sure."
Those two are set to meet Dec. 30 at MGM Grand Garden Arena in Las Vegas.
Henderson beats Guida to earn title shot
Takedown defense, striking, patience and physical strength were all put on display by Benson Henderson during his lightweight title eliminator against Clay Guida.
In a high-energy, fast-paced bout, Henderson was the more effective fighter, enabling him to come away with a unanimous decision and a title shot against 155-pound champion Frankie Edgar.
The judges scored it 29-28, 30-27 and 30-27. ESPN.com scored it 30-27 for Henderson.
No date had been set for Edgar-Henderson. But that didn't prevent Henderson (15-2) from letting the champion know that he is eager to meet him in the cage.
"Frankie Edgar, we've got a date," said Henderson, a former WEC lightweight champion who is 3-0 in UFC. "Let's do it baby."
Guida had come into the eliminator on a four-fight win streak. In his most recent fight, he manhandled Anthony Pettis -- the last man to defeat Henderson.
But on this night, Guida (29-12) could not find an answer for Henderson. Though Guida was behind heading into the final round, he nearly pulled out a victory by almost securing a choke.
Henderson, however, never lost his cool in the fight and was able to escaped danger. He finished with a flurry of punches to seal the win.
Poirier forces Garza to tap in second round
Poirier controlled Garza standing and on the ground. He also proved to be the physically stronger fighter, pushing Garza around when the two were in close quarters.
"I didn't cut any corners in training camp," Poirier said after applying a D'arce choke at the 1:32 mark that improved his record to 11-1 (3-0 in UFC). "That choke is really hard to get from half-guard."
Garza, who was victorious in his two previous UFC appearances, slipped to 11-2 overall.
Mourning Lamas submits Swanson
Ricardo Lamas fought with a heavy heart against Cub Swanson, but he was determined to walk away victorious. That determination paid off as he submitted Swanson in the second round of their featherweight bout.
"My grandma passed a week ago today," Lamas said after finishing Swanson with an arm triangle at the 2:16 mark. "I want to dedicate this fight to her."
Swanson nearly finished Lamas in the first round with a guillotine, but he was unable to hold the choke. Lamas (11-2) admitted after the fight he was in trouble.
"I wasn't tapping. He was going to have to put me out," Lamas said. "It was very tight. Good thing he let go, because I couldn't breathe."
Swanson, who was fighting for the first time in just over a year, fell to 15-5.
Johnson finishes Harvison in first
"I was trying not to get my butt whipped," Johnson said after improving to 13-9. "The last time I came out here, Amir Sadollah beat me; I wanted to show I could do better."
Johnson landed a left hook on the chin that sent Harvison to the canvas. The force of the punch left Johnson convinced his opponent would not recover and he began to celebrate. The referee did not jump in immediately, however, and Johnson landed two more punches to his grounded foe.
Harvison (9-4) has dropped two fights in a row.
Uyenoyama beats Yamamoto in UFC debut
Norifumi Yamamoto is still looking for his first win in UFC competition after dropping a unanimous decision to Darren Uyenoyama in a bantamweight bout.
The judges scored the fight for Uyenoyama 30-36, 30-27 and 30-26. ESPN.com had Uyenoyama winning the fight 30-27.
Yamamoto is 0-2 inside the Octagon and 18-5 (one no contest) overall. He was nearly submitted in the first round but was saved by the horn.
"I thought he might have [tapped]," Uyenoyama said. "I was seeing it from the back, so I didn't have a good point of view."
Uyenoyama, who was making his UFC debut, improved to 7-3.
Peralta gets heads-up on Semerzier
It wasn't your classic TKO, but Robert Peralta isn't complaining. He stopped featherweight Mackens Semerzier at 1:54 of the third round when their heads accidentally clashed.
The fighters were exchanging strikes at the time their heads came together. Semerzier got the worst of the head-butt, falling to the ground as Peralta pounced on him.
Peralta (16-3) extended his win streak to nine. Semerzier is 6-4.
Caceres beats Escovedo for first UFC win
All three judges scored the fight 30-27 for Caceres, as did ESPN.com.
The win improved Caceres to 6-4. He is 1-2 inside the Octagon. Caceres competed at featherweight in his previous two UFC bouts.
Escovedo (17-9) lost his third straight UFC fight.
Bradley still can't find answer for Pierce
The fight was a bit closer this time, but Mike Pierce made it two in a row against Paul Bradley with a split-decision win in a welterweight bout.
One judge scored it 29-28 for Bradley, while the other two saw it in favor of Pierce, 29-28 and 30-27. ESPN.com had it for Pierce 29-28.
Pierce (13-4) defeated Bradley (18-4) by unanimous decision in a non-UFC bout in April 2009.
Lucas overwhelmed in UFC debut
Fighting in the UFC for the first time proved difficult for light heavyweight Matt Lucas. He ate elbows and knees repeatedly from Aaron Rosa, and found it hard holding on to his mouthpiece.
Lucas (14-3) looked unprepared and his five-fight win streak came to an end as he fell 28-28, 30-26 and 30-26. ESPN.com scored it 30-26 for Rosa.
Rosa, who moved to light heavyweight after competing at heavyweight, improved to 17-4.
Franklin McNeil covers MMA and boxing for ESPN.com. He also appears regularly on "MMA Live." Follow him on Twitter at http://twitter.com/Franklin_McNeil.