By Keith Idec

Kell Brook has boxed above 150 pounds just eight times during his 36-fight, 11½-year pro career.

The unbeaten IBF welterweight champion hasn’t fought higher than 155 pounds, either. England’s Brook still didn’t request a catch weight for his middleweight title shot against Gennady Golovkin.

Unlike the Canelo Alvarez-Amir Khan WBC middleweight title fight May 7 in Las Vegas, contested at a catch weight of 155 pounds, the contract weight for the Golovkin-Brook championship match September 10 in London is boxing’s middleweight limit of 160 pounds.

“A hundred and sixty was always the weight that was discussed, and that’s part of Brook making history,” said Tom Loeffler, managing director for K2 Promotions, Golovkin’s promoter. “If they would’ve asked for a catch weight, it would’ve taken a lot of the luster off of it. So we give him a lot of credit for that.

“And I also made it clear to [Brook promoter] Eddie [Hearn] that Gennady holds four titles in the middleweight division and it doesn’t make sense for him to go down in weight. We agreed to the deal in less than two hours, and it just took us two days to finalize all the details with Gennady.”

The only restriction for either fighter is the IBF’s usual second-day weigh-in limitation. Combatants in IBF title fights cannot weigh more than 10 pounds over a division’s limit during a second weigh-in the morning of their fight.

The 34-year-old Golovkin (35-0, 32 KOs) will defend his IBF, WBA, IBO and WBC middleweight titles against the 30-year-old Brook (36-0, 25 KOs) at O2 Arena (HBO; Sky Sports Box Office).

Keith Idec covers boxing for The Record and Herald News, of Woodland Park, N.J., and BoxingScene.com. He can be reached on Twitter @Idecboxing.