The Ukrainian is the first lineal champion since Lennox Lewis in 1999.
The Hamiltonian extended his unbeaten professional streak to nine in Saudi Arabia.
Tyson Fury weighed in almost 20kg lighter than his last bout against Francis Ngannou.
The last boxer to was all the belts was Brit Lennox Lewis in 1999.
'Lieutenant Dan' Hennessey called the wrong winner on the undercard of Lamachenko-Kambosos at Perth.
Just days out from their heavyweight title blockbuster, John Fury appears to headbutt a member of Usyk's team he claims "disrespected" his son.
Francis Ngannou has paid tribute to son Kobe in a social media post.
Mea Motu knocked out her Thai opponent in the second round to retain her IBO bantamweight title.
It appears a rematch with Zhang may not be the Kiwi heavyweight's next date in the ring.
It comes after his majority decision victory over China's Zhilei Zhang.
The Brit now wants a crack at the winner of Tyson Fury v Oleksandr Usyk.
Parker was knocked down twice but was the far more active fighter throughout.
Mike Tyson said it would be 'fun' to take on the social media celebrity, turned pro boxer.
The winner will walk away with the WBO interim heavyweight title.
It's not the first time the artist has taken jabs at his friend-turned-foe.
"There are no health benefits of tackling - and there are no health benefits of being struck in the head."
The Brit has delayed the unification bout for the second time, due to injury.
The former world champion has faced - and lost to - his rival before, as an amateur.
A freak sparring accident to the Brit has forced a postponement to May.
Kiwi David Nyika was scheduled to meet an unconfirmed opponent on the undercard.