World heavyweight champion Vladimir Klitsckho has postponed next month's IBF title bout with Bulgarian Kubrat Pulev after sustaining an injury in training.
"I am very disappointed the fight will not go ahead," the 38-year-old Ukrainian said in a statement. "I am in top form and had a great training camp."
Klitschko, who also holds the WBO, WBA and IBO belts and has won 62 of his 65 bouts, tore bicep muscles during training in Austria.
The fight was due to be held on 6 September in the champion's Hamburg base. It will now be staged at the same venue later this year.
Pulev, 33, who has recorded 11 knockouts from 20 wins, became the IBF international champion in 2011 and European champion in 2012.