Las Vegas, Nevada – For the first time in the history of the Ultimate Fighting Championship®, a UFC® champion has refused to face an alternative challenger after an injury to his original opponent, forcing the organization to cancel an event.

After challenger Dan Henderson suffered a torn medial collateral ligament in his right knee, UFC light heavyweight champion Jon Jones refused an alternative opponent, forcing UFC president Dana White to cancel the entire UFC 151 card at the Mandalay Bay Events Center in Las Vegas next Saturday.

On a conference call today, White said Jones refused to fight two-time middleweight title challenger Chael Sonnen, whom he proposed as a replacement for Henderson for the September 1 event.

"This is probably one of my all-time lows as being president of UFC,” White said. “Dan Henderson tried to train, he continued to work out and saw a doctor, but there was nothing we could do to save that fight.

“But Chael Sonnen stepped up accepted the fight with Jon Jones last night. As of 8pm last night, we thought we had a fight fans would love to see. Then at about 9pm the one thing I never thought would happen in a million years happened. Jon Jones said, “I won't fight Chael Sonnen on eight days notice’. That has never happened in the history of the UFC, a guy who is a champion, and a guy who is supposed to be one of the best fighters in the world, pound-for-pound, refuses to fight.

“Chael is just coming up from 185pounds. He said that not only would he face Jones in eight days, he’d jump in a plane to Vegas and fight him that night if he was asked to. Jon Jones said 'I'm not fighting Chael Sonnen with eight days' notice. Jones’s trainer, Greg Jackson, told Jon that taking the fight with Chael would be the biggest mistake of his life. That’s what he told Jon Jones. Let me tell you, this guy (Greg Jackson) is a sport killer.

“When you are a champion, much less one of the guys who is supposed to be one of the best pound-for-pound fighters in the world, you are supposed to step up. Jon Jones is a guy a lot of fans don’t like, and I don’t think this is going to make him any more popular. Lorenzo Fertitta (UFC chairman and CEO) and I are disgusted with Jon Jones and Greg Jackson.”

Ticket refunds are available at the point of purchase. Jones will now rematch with karate expert Lyoto Machida in the new main event of UFC 152 in Toronto, Canada. UPDATE: Later in the day, the UFC announced that Machida had opted not to take the fight. Instead, the UFC 152 headlining title fight will be between Jon Jones and Vitor Belfort.

White explained: “UFC 151 will be remembered as the event Jon Jones and Greg Jackson murdered.”

White said the fall-out for the UFC, its partners, fans and fighters was ‘huge’.

"It’s major, major deal," said White. "We lose a lot of money, money that’s already been spent. We’re eight days out. We’ve spent tons of money on this fight. How long and how far it goes and how bad it hurts I don’t know because it’s the first time we’ve done it.

“One thing that you really have to think about are the fighters on the undercard. Sure, Jon Jones is rich what does he care if he cancels the fight? But 20 other fighters on the card added up to almost a half a million dollars in purse money that Jones and Greg Jackson’s decision stole from them. No champion or headliner in UFC history has ever done that. As difficult as Tito Ortiz could be… even Tito never bailed on a fight.”

“Many people, from fans to PPV distributors, TV networks, sponsors, and more importantly fighters who are working hard to support their families and build their careers are hurt badly by this selfish decision.”

Henderson said: “This is the first time that the champion wouldn't step up and fight, and I was pretty shocked to hear that. It's not like he's injured. It's unbelievable to me that he wouldn't take that 'the show must go on' attitude. If there was any way I could have gone, and any way that I thought I could give myself a chance to compete, I would have done that."

Sonnen said: "I was shocked that he refused to fight me. I had already gone to the gym to train. He had a chance look prove himself a champion, an ultimate fighter, and he didn’t take that chance.”