Fast-rising light heavyweight contender Phil Davis pulled out his Aug. 6 fight in Philadelphia at UFC 133 because of a knee injury.
Davis (9-0) was scheduled to fight Rashad Evans.
UFC president Dana White confirmed the injury to The Canadian Press.
For Evans (20-1-1), this is another setback on his crazy, winding road toward another title shot. Evans beat Quinton "Rampage" Jackson on May 29, 2010, and was earned a title shot against then-champion Mauricio "Shogun" Rua.
Rua injured his knee, and Evans chose to wait it out. Then, six weeks before the fight was supposed to take place at UFC 128 in New Jersey on March 19, Evans injured his knee. Jon Jones, Evans' training partner, was given the title shot.
Jones beat Rua, said he would fight his teammate, then had to scrap the UFC 133 defense against Evans because of a hand injury. Jones is now scheduled to defend his title against Jackson at UFC 135 on Sept. 24, and Evans is still waiting for an opponent.
Lyoto Machida is rumored to be Evans' replacement opponent, but the UFC has yet to make an official announcement. It was Machida who took Evans' title on May 23, 2009.