New Zealander Joseph Parker will fight the undisputed heavyweight world champion winner of the Oleksandr Usyk v Daniel Dubois fight in London in July, promoter Frank Warren said on Tuesday. Unbeaten Ukrainian Usyk — the WBA, WBC and WBO champion — and Britain’s IBF champion Dubois are fighting a four-belt showdown at London’s Wembley Stadium on July 19. Dubois, 27, had been set to face former WBO world champion and current interim champion Parker in Saudi Arabia last February but withdrew from the fight due to illness. Warren’s Queensberry Promotions represents both Parker and Dubois. “With Joe Parker, the WBO just put a mandate out saying that the winner of this fight (Usyk v Dubois) has to defend against the WBO mandatory challenger, which is Joe Parker,” Warren told Sky Sports television. “People might be saying ‘Oh, Joe must be peed off he’s not fighting Daniel”. “Well, he’ll be fighting for four belts now. Whoever wins it (the undisputed title fight), which I hope is going to be our man (Dubois), they’ll be challenging for four belts so he’s in a better place.”