LAS VEGAS – Anderson Silva's amazing run of 2,458 days as UFC middleweight champion ended with him lying flat on his back, knocked out, as the result of an arrogant and short-sighted decision.

In the end, he turned out to be not as good as he thought he was.

Silva kept his hands at side and frequently urged Chris Weidman to fight. He gave Weidman several free shots at his chin.

In the second, Silva put his hands down, and was moving at the waist, avoiding most of the punches. But he didn't avoid them all, and it led to one of the most stunning finishes in UFC history.

Weidman caught Silva on the chin with a left hook while Silva's hands were at his waist. He finished the fight quickly on the ground and claimed the middleweight belt, giving the UFC its first new 185-pound champion since Oct. 14, 2006, when Silva stopped Rich Franklin.

Silva had gone 16-0 in the UFC and had won 10 consecutive title bouts since his last loss, via disqualification, to Yushin Okami at Rumble on the Rock 8 on Jan. 20, 2006, in Honolulu.

Many of his peers were picking Weidman to dethrone him on Saturday, but few saw it coming the way it did. After an early Weidman takedown, Silva inexplicably kept his hands down and kept shouting to Weidman to fight.

As he walked back to his corner after the first, Weidman was shaking his head.

He was not happy.

"It pisses me off when someone does that to me and I knew sooner or later, I'd get him," Weidman said.

He got him in the second. Silva was about eight feet from the cage and again, dropped his hands. Silva dodged three or four of Weidman's punches completely, but then a right grazed him.

That didn't seem to have an impact, but a crushing left hook landed on the point of Silva's chin and changed the course of UFC history.

The top fighter in the world, the man many had proclaimed as the greatest in UFC history, was out in an instant, his magnificent reign shockingly over. It also blew a potential super fight between Silva and light heavyweight champion Jon Jones, the man who now has to be regarded universally as the top pound-for-pound fighter in the world.

Silva said he did not want a rematch, but said he would continue to fight.

"Chris Weidman has my respect," Silva said. "He's the best. I did my best, but he's the best."

Weidman, who came to the ring draped in the American flag, could hardly believe what had just occurred.

"I felt destined, but it still felt far-fetched," Weidman said. "I imagined it so many times in my head, but it still feels surreal."

Frankie Edgar def. Charles Oliveira by UD

Former lightweight champion Frankie Edgar, fighting in a non-title fight for the first time after seven consecutive championships matches, pulled out a close unanimous-decision victory over Charles Oliveira in an electric back-and-forth fight.

It was typical Edgar, as he pushed the pace and tried to make it a brawl. He mixed in his wrestling and scored several takedowns, but Oliveira fought back hard.

Oliveira had a four-inch height advantage, and it was difficult for Edgar to get close enough to land his blows.

But he showed the guts that have made him one of the most popular fighters in the division and found a way to get inside Oliveira's jab.

Tim Kennedy def. Roger Gracie by UD

In each man's UFC debut, Tim Kennedy ground out a very slow, unimpressive victory over Roger Gracie in a middleweight match. Gracie got Kennedy's back in the first round, but couldn't get close to a submission.

Neither man did much after that, but Gracie seemed to gas early, and Kennedy essentially won the bout by pushing the pace. There were no big punches or kicks landed and nothing close to a submission.

Kennedy won by scores of 30-27 twice and 29-28.

"I'm really disappointed [because] I hate going to decisions," Kennedy said. "I guess UFC jitters are real. It's a big stage and I feel like I really let down my fans."

Mark Munoz def. Tim Boetsch by UD

Mark Munoz turned in one of the best performances of his UFC career, rebounding to trounce Tim Boetsch in a three-round middleweight bout.

Munoz was knocked out in a No. 1 contender's fight last July with Weidman and went into a depression after that. He ballooned way up in weight, and said he used food as comfort.

But he was dominant Saturday, using his wrestling and some good ground-and-pound to overwhelm Boetsch. Judges had it 30-26, 30-27 and 29-28 for Munoz.

"I am living proof of what you can do with determination, will and desire," Munoz said.

Boetsch was surprisingly non-aggressive, and he was mystified later by the way he performed.

"I'm not sure what I was thinking out there," he said. "I was just a little bit off. My timing just wasn't there. I had the cardio to keep going, but never pulled the trigger."

Cub Swanson def. Dennis Siver by KO3

Cub Swanson is a guy who did pull the trigger. He won his fifth in a row and remained near the top of the featherweight division with an impressive third-round stoppage of Dennis Siver.

Swanson landed a clean straight right hand that landed on the chin and clearly hurt Siver badly. He followed with another right that decked Siver and finished him with huge shots from the top.

The oddity was that referee Herb Dean was standing right next to them, and Swanson twice raised his arms, as if to ask what else he had to do. Dean finally stopped it at 2:24 of the third.

"I tried to go after him right away, but had to step back and compose myself to regain the energy I needed in order to finish the fight," Swanson said. "I'm the number one contender in the division, [and] when I get that call for my next fight, I will be ready to go for the belt."

Siver was clearly disappointed.

"I thought I won the first two rounds, but it's MMA and you never know," Siver said. "One punch can change your career."

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• Mark Munoz dominant in UFC return