Daniel Dubois left Filip Hrgovic battered in a brutal stoppage to cement his name in the title mix.
Dubois needed a KO to seal the 5 vs 5 tournament win for promoter Frank Warren, and secure the IBF interim heavyweight world title and a mandatory shot at Oleksandr Usyk.
And it was the Briton who rallied to an incredible stoppage, with the doctor stepping in to halt the showdown in the eighth.
It ensured that Hearn lost the tournament to rival promoter Warren at 8-0 down, and the Queensberry stable pocketed a huge $3 million prize fund.
The future of the IBF title is currently held up, with the winner now having the potential to be crowned champion without stepping in the ring again.
Usyk was expected to be stripped of the title, but is awaiting to discover if he will be granted an ‘exemption’.
This would mean that Usyk would keep hold of the belt and defend undisputed stats in his December 21 rematch with Tyson Fury.
The fight began at a fiery and powerful early tempo, with Hrgovic landing some huge right hands in the opener, with ‘Dynamite’ looking open due to his aggressive approach.
It looked as if it almost certainly wouldn’t go the distance, with the Briton and Croatian both absorbing early punishment in big exchanges.
A frightening trade of power punches continued with Dubois landing well and he opened up a cut under the right eye of Hrgovic in the second.
The third and fourth stanzas continued with Dubois absorbing a lot of work, but also landing some huge shots, with high-stakes in the heavyweight division clearly present.
Hrgovic began to tire as blood trickled from his eye, with the ferocious early tempo starting to catch up with the fighters who continued to trade.
Dubois upped the ante against a seriously fatigued Hrgovic in the seventh round, who somehow survived after receiving punch after punch as the bell sounded.
But it was the eighth where Hrgovic met his match, as the doctor decided to halt the contest with cuts open above both of the undefeated star’s eyes.
The onslaught had continued, and it was simply too much for Dubois, who now has the option of Joshua or Usyk in his next outing.
Any all-British clash with Joshua is set to take place in September, with AJ sat at ringside to see his rival’s warrior-like display.