Former WBC heavyweight champion Vitali Klitschko has postponed his comeback fight against Jameel McCline after suffering a back injury.
Klitschko's last fight was in December 2004
The 36-year-old was due to fight for the first time in three years on 22 September but underwent emergency spinal disc surgery on Saturday.
"I can't believe my bad luck," Klitschko told German newspaper Bild.
Klitschko's last fight was in December 2004 when he stopped Danny Williams in the eighth round.
A string of injuries, including a serious knee injury, forced him to retire in November 2005 before announcing his comeback earlier this year.
He is expected to be sidelined for six weeks after his latest setback.