Vitali Klitschko has endured yet another injury that will prevent him from defending his WBC heavyweight championship against Hasim Rahman.

Their title fight set for Saturday at the Thomas & Mack Center in Las Vegas is postponed after Klitschko reportedly suffered a knee injury while sparring in Los Angeles on Thursday.

Surgeon Dr. Tony Daly examined Klitschko early yesterday. He diagnosed a sprain and suggested Klitschko attempt to fight with a knee brace, but when Klitschko tried to spar with the brace yesterday afternoon he said the knee was restricting his side-to-side movement.

Promoters for the fight said the bout would be rescheduled at a date to be announced next week. Two other proposed meetings between the two heavyweights were shelved because of various other injuries to Klitschko, who hasn’t fought in 12 months.