Isaac Chamberlain to spar cruiserweight champion Oleksandr Usyk

Isaac Chamberlain will spar world champion Oleksandr Usyk, suggesting it will be harder than facing London rival Lawrence Okolie.

The Brixton cruiserweight is heading to Kiev to help the unbeaten WBO king Usyk prepare for his World Boxing Super Series fight with two-time champion Marco Huck.

Chamberlain, who has sparred with WBC heavyweight champion Deontay Wilder and Polish cruiserweight Mateusz Masternak in the past, is more interested in trading punches with the Ukrainian than exchanging verbal jabs with Okolie.

"The fight with Okolie will happen down the line but here and now all I am focused on is going to spar the best cruiserweight in the world," he told Sky Sports.

"It will be tough but I am going out there to learn and hold my own against him.

"I've sparred with the 'Bronze Bomber' already and I wouldn't be surprised if Usyk is even tougher in camp. I don't know what to expect, but it'll probably be harder than taking on Okolie."

Usyk and has been joined by fellow world cruiserweight champions Mairis Briedis (WBC) and Murat Gassiev (IBF) in the eight-man tournament.

The Ukrainian's opening fight with Huck is on September 9 and Chamberlain will spend at least three weeks sparring with the London 2012 Olympic gold medalist.

"It is invaluable experience, the sort of experience you won't get anywhere else," he said.

"I think right now he is the best cruiserweight in the world and to mix with that sort of fighter, so early in my career, makes it such an amazing experience.

"I just can't wait to learn what he's got, pick up all sorts of tips and I am going to pick his brain as well. I might need to get a translator there, but I will pick and pick.

"Usyk will not take it easy, I am sure. Masternak, when I was sparring him, went straight for me. It's not a joke, so I have to bring my A-game all the time.

"The way Usyk moves, his combinations and the angle he puts his opponents in, shows that he can be defensive-minded but he attacks very well.

"He's just like a big (Vasyl) Lomachenko, so if I can learn or add his tricks to my repertoire, it will be really good. I will use it for my own benefit, I am not just there for them."