Joe Joyce and Joseph Parker will now fight for the interim world title when they meet at the AO Arena in Manchester on September 24.
The stakes are now even higher ahead of what was already a highly-anticipated fight between the two heavyweights.
A request from promoters for Joyce and Parker was approved by the WBO, amid concerns that the winner would not be given a due mandatory title shot.
Joyce and Parker, ranked one and two respectively, had originally been scheduled to fight on July 2, but the latter’s partnership with BOXXER led to a postponement.
World heavyweight champion Parker has admitted to struggling with motivation after becoming a father for the first time.