Dominic Ingle waved the white towel from the corner after the British challenger had suffered damage to his right eye in an explosive encounter at The O2 Arena on Saturday night.
Brook had been caught early on by Golovkin, only to return the favour shortly after – and up against one of the hardest hitters in the game, the vision issue seemed to have the decisive impact after a barrage of unanswered shots in the fifth.
Ingle will be criticised by some for pulling the ‘Special One’ out, but Brook had been troubled from as early as the opening minutes. By the fifth, he had no defence up – never mind full vision – as knockout specialist Golovkin showed his power is savage, to say the least.
However, Brook proved that class can match power and, at times, overhaul raw brutality, To learn that the judges had him ahead on their scorecards until the towel came in made a mockery of those who claimed that Brook would be blown away by the middleweight kingpin.
There were multiple winners. Golovkin made it 36-0-KO32 with another ruthless show, while his challenger emerged with extreme credit and boxing fans around the world saw a classic clash that will live long in the memory.
The opening salvo was what we expected, Golovkin marching forward, landing body shots and the odd straight right, closing down the gap and pushing Brook back. But it clearly was not going to be over in a flash, as the Sheffield fighter picked him off with a lovely left.
The next blow, though, was a typical left to the ribs that left Brook open for a simple shot to the head that momentarily put him on unsteady legs. Brook regrouped, though, and somehow closed the round with two more of his left uppercuts and a hook to almost redress the balance.
The challenger started the second round in similar fashion – on the offensive – with another shot from his waist, a straight right and another left uppercut catching Golovkin, marking his face and even bloodying his nose.
It was then that Brook started to scratch that right eye, trying to refocus it, yet even though Golovkin began closing him down more and more, the champion was as frustrated as he was fearsome in his usual approach.
Brook slipped over at the start of the third, suggesting his balance was no match for Golovkin’s bullying, yet he still gave as good as he got, at times happy to sit in the pocket and counter again, even in the next two non-stop, yet less dramatic rounds.
By then, the eye seemed to be bothering Brook more, while Golovkin was in almost robotic mode, and the fifth saw him trap the British star in a neutral corner and unleash multiple blows – the left to the body proving he had not damaged his chief weapon six weeks ago, and the right highlighting both his hands do damage.
Ingle was then calling an end to the contest, leaving the crowd stunned. But even with an eye socket damaged, Brook remained standing and was able to leave the ring with his head held high.