Phil Davis suffers a knee injury in training and has pulled out of his upcoming light heavyweight title contention bout with Rashad Evans at UFC 133. Possible replacements, Tito Ortiz and Lyoto Machida have declined to step in to face Evans according to mmamania.com.

"The fight is very close and for a professional matter we can't accept it. We want to make the best match and there is remaining just a few weeks and it wouldn't be fair with the fans to do a bad performance" Caju Freitas, member of Machida's camp, said.

Those sediments were echoed by Machida's manager, Ed Soares, further confirming Machida's absence from the bout despite earlier reports of a Machida and Evans rematch.

Similarly, Ortiz cited lack of preparation time as his reasons for not taking the fight.

"I have a life and things to take care of. The fight game is about making the right choices of my career. If you knew what I have been going through you all would understand. Peaking for a fight is what makes a fighter unstoppable! Timing is everything in life. This is a rebuild year for me not do or die. The time will come again!" Ortiz said on his twitter account.

The fallout of Davis' injury has left Evans without an opponent and his 2011 debut will have to wait unless UFC matchmaker, Joe Silva, can find a fighter willing to take the bout on less than a month's notice.

Evans has not fought since mid 2010 when he last defeated arch rival, Quinton Jackson, at UFC 114 via unanimous decision.

UFC 133 on August 6 at the Wells Fargo Center in Philadelphia, Pennsylvania will now likely be headlined by Rich Franklin and Antonio Rogerio Nogueira.