The 26-year-old made a miserable start to the fourth fight in the 5v5 tournament, eating right hands like they were hamburgers.

But in the seventh round he bit down on his gumshield and rescued his career, to make it 8-0 to Warren and potentially set up a September super-fight with Anthony Joshua. The opener started evenly enough but Dubois suddenly decided to stop defending against the 31-year-old Croatian’s textbook right hand.

At least half a dozen basic right hands flew in and landed on the Brit’s vulnerable skull. It was a worrying start for the mild-mannered Londoner.

The second went the same way and Dubois’ left eye started to swell and close, with so much of the fight still to go. Thankfully for his concerned fans at ringside, Dubois landed a couple of right hands and a left hook right on the bell that slashed a cut over Hrgovic’s right eye.

Bloodied Hrgovic looked to be flagging as early as the third but Dynamite Dan still let him land every right hand he threw. Dubois infuriatingly refused to hold his lead left hand up and protect his face, so Hrgovic kept pinging him with straight rights but none of them seemed to be doing much damage. The clear harm had been done to Hrgovic’s eye that should have been like a bright red target for Dubois to attack.

Hrgovic landed a thudding overhand right just as the bell to end the fifth rang, slapping the sweat off Dubois’ head, yet the tough Englishman somehow shrugged it off and tried to exchange fire before walking neatly to his corner Dubois, who rightly had his heart questioned after surrendering in defeats to Joe Joyce and Oleksandr Usyk, never stopped trying and refused to wilt despite the utter rout of right hands he ate.

The seventh might have been the most seminal of Dubois’ career as he completely ripped up the script and pushed Hrgovic to the brink. Dubois landed a range of shots, never shipped a single right and had the 2016 Olympic bronze winner buzzed and saved by the bell, with both eyes now slashed with deep cuts.

The eigth round had barely kicked off before the ref walked Hrgovic into a neutral corner and called up the doctor. After a brief exam of both eyes and a whisper in the ref’s ear, the fight was called off and Dubois awarded the incredible win for Dubois and his loyal mentor who rebuilt him after two painful defeats.

He has now set up a clash with Joshua and Dubois said of the potential fight: “I hope the next opponent would be AJ so bring it on. This is my era and this is my time.” Dubois added: “I have full respect for the guy, to come through that was a learning experience. I’m glad I got the belt and on to the next.

“I was a bit cold to start off with, I had the corner advice, Frank Warren and my dad.

“I ate some shots but it was only to wake me up. The first few shots stung but they woke me up.

“I’m so proud of myself. It is all a learning experience. We are back on top.

“It has felt like a rollercoaster.”