Sheffield’s Brook, unbeaten in 36 professional bouts, is moving up two weight divisions to take on the fearsome Golovkin, who is unbeaten in 35 fights with 32 knockouts to his name.
The 30-year-old is drawing inspiration from welterweight great Leonard, who shrugged off retirement in 1987 to beat world middleweight champion Marvin Hagler.
“I want to do what Leonard did with Hagler – use my speed, my footwork and box the perfect fight,” said Brook.
“I do fear him, of course I do. I know he’s a big puncher and that nobody wants to fight him for a reason. But the fear is positive because it’s going to make me super-sharp with cat-like reactions.
“You could see the fear in Leonard’s eyes when he was in with Hagler, that’s why he was so sharp and zoomed in.”
Brook is looking to fare better than fellow Briton Amir Khan when he jumped two weight divisions to take on WBC middleweight champion Saul Alvarez in May. Khan was knocked out in six rounds.