The main event of UFC 152 was UFC Light Heavyweight Champion Jon Jones facing former champion Vitor Belfort.
Originally, Jones was set to defend his title against Dan Henderson at UFC 151 on September 1, 2012 in Las Vegas, Nevada, but UFC President Dana White announced on August 23, 2012 that Henderson had a tear in his MCL and would not be able to compete.
It was then revealed that Jones declined a fight against Chael Sonnen, who offered to take the fight on eight days notice. As a result, the event was cancelled. This marked the first time the UFC had cancelled an event, with the official fight card having been announced, in the organization’s history.
Following the cancellation of the event, White said that UFC 151 simply will not exist. Jones was set to face Lyoto Machida in a rematch at this event after the cancellation of that event, but Machida declined the fight. Subsequently, Belfort was chosen to take Machida’s place.
The co-main event, originally serving as the evening’s main event, featured Joseph Benavidez taking on Demetrious Johnson in the finals of a four man tournament to determine the inaugural UFC Flyweight Champion. Benavidez earned the right to fight for the championship by defeating Yasuhiro Urushitani by second round TKO; whereas Johnson defeated Ian McCall by unanimous decision in a rematch of their original semifinal fight which ended, with controversy, in a draw.
Here are the results from the event: