Dubois, who retained his IBF heavyweight title, dominated the fight from the outset, dropping Joshua multiple times with powerful punches.
Usyk has remained unbeaten, retaining the WBA, WBO, IBF and IBO heavyweight titles.
With Saturday’s win, Fury extended his unbeaten record, out punching and handing Chisora his 13th defeat in 46 career fights.
Oleksandr Usyk’s mandatory commitments with IBF challenger Filip Hrgovic will have no bearing on a bout against Britain’s Tyson Fury to unify the world heavyweight titles.
If the fight did happen, the winner would become the first undisputed heavyweight champion since Lennox Lewis from 1999 to 2000.
Joshua was defeated by Ukraine’s Oleksandr Usyk on a surprise split points decision after 12 hard rounds to retain his WBA, WBO, IBF and IBO world heavyweight boxing belts in Jeddah.
“If you know my story, you know I’m the comeback king. You can put me down, but it’s difficult to keep me down,” said Joshua.
Last September, Usyk defeated Joshua, a two-time world champion, claiming the WBA (Super), IBF and WBO heavyweight titles.
The former heavyweight champion called the fight for name sake Tyson Fury, citing AJ’s slow punch speed.
The two fights will take place this year with first fight holding in June or July.
