IBF, WBO and IBO heavyweight champion Wladimir Klitschko suffered a torn left biceps, forcing him to postpone next month's title defense against Kubrat Pulev, reports Dan Rafael of ESPN.com.
The bout was scheduled for Sept. 6 in Hamburg, Germany.
"I am very disappointed that the fight cannot take place as planned,” Klitschko said in a statement. "Of course, I'm sorry for the fans, but also for my opponent Kubrat Pulev, who was certainly training as intensely as I do.
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Klitschko's manager Bernd Boente told ESPN.com the fight will be rescheduled for November.
Klitschko (62-3, 53 KOs) has made 16 straight successful title defenses, last losing in April 2004 when he was knocked out by Lamon Brewster in the fifth round. He last fought Alex Leapai in April, scoring a fifth-round TKO.
Pulev (20-0, 11 KOs) beat Tony Thompson by unanimous decision last August, earning a mandatory title shot.
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