Alexander Usyk will not defend his IBF World Championship title. Britain's Anthony Joshua and Daniel Dubois will fight for the vacant crown on September 21 in London.
Usyk will return to the ring on December 21 in Riyadh. This will be the rematch of the world championship duel that the Ukrainian won on points against Britain's Tyson Fury in the Saudi Arabian capital in mid-May.
Usyk's victory secured him the IBF, WBO, WBA and WBC belts.