The 36-year-old welterweight calls time on his illustrious career three months after beating arch-rival Amir Khan with a ferocious sixth-round stoppage in Manchester.
Brook, 36, retires with an impressive record of 40 wins and 28 knockouts from 43 professional fights.
The Sheffield favourite’s only pro defeats came at the hands of truly top-tier opposition in Terence Crawford, Errol Spence Jr and Gennady Golovkin.
Brook reigned as the IBF welterweight world champion after defeating Shawn Porter on a memorable night in California in 2014, reigning until his defeat by Spence in May 2017.
His retirement ends any speculation over a rematch with Khan, who has yet to decide his own future, or other lucrative all-British showdowns with the likes of Chris Eubank Jr and Conor Benn.
“I’ve had a long chat with my family and my parents, and it’s over for me. I’ll never box again,” Brook told The Telegraph.
“It’s a little emotional to be actually saying this out loud. My mam [Julie] is relieved. I think everyone around me is pleased.
“Truth is, boxing is a very very tough, dangerous sport, one in which you can be legally killed in the ring, and I’ve finished now with all my faculties intact.”
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