Gennady Golovkin will fight Kell Brook live on Sky Sports Box Office on September 10

Gennady Golovkin's promoter says his bout with Kell Brook solves a problem fighters share - that opponents in their own weight divisions do not want to face them.

Welterweight Brook (36-0-KO25) will fight the Kazakh middleweight at the 02 Arena and live on Sky Sports Box Office on September 10, with all four of Golovkin's world titles on the line.

Brook's decision to accept the fight has been questioned by many people within the sport, but the 30-year-old has said he plans to be a "different animal" during the contest.

We are putting the feelers out over the next few weeks to secure the next move. Eddie Hearn

Golovkin's promoter Tom Loeffler feels the fact both fighters boast undefeated records and reputations as fearsome competitors meant they were limited in terms of potential opponents in their own weight divisions.

"Kell wasn't really on our radar screen because he's a welterweight, so we didn't expect him to be a realistic opponent," he told Sky Sports News HQ.

IBF Welterweight champion Kell Brook says he is excited to move up two weight divisions IBF Welterweight champion Kell Brook says he is excited to move up two weight divisions

"But I think Kell had been thinking about this fight for a while because he's had a challenge getting the big welterweight names to fight him, just like we've had the same challenge getting big middleweight names to fight Gennady.

"So this really solves the problem for both fighters. It's a massive event. I was at the fight in the United States when Kell beat Porter and he made a huge statement in that fight."

Loeffler says the dominant opinion of Brook within the Golovkin camp is one of respect for taking on such a difficult-looking fight, and says the Sheffield star will not be underestimated.

Tony Bellew believes Brook will provide Golovkin with a new challenge when they fight in September Tony Bellew believes Brook will provide Golovkin with a new challenge when they fight in September

"Gennady's always 100 per cent prepared," he said. "I've never seen any athlete train as hard as he does and there's a reason behind his success.

"He's consistent with every fight and he never underestimates any opponent. With Kell stepping up from welterweight it takes it to a whole new level and I think that's why the fans are so excited.

"You've got to give him a lot of respect for that."

Kell Brook will challenge for Gennady Golovkin's world middleweight titles on September 10 at London's 02 Arena, live on Sky Sports Box Office.