The former two-time world champion was the pre-fight favourite, but was floored multiple times in front of 96,000 fans by the IBF heavyweight world champion in the early stages.

Yet Joshua stubbornly refused to give up, and wobbled his foe early in the fifth himself before a right-hook counter-punch handed him just a second loss by KO in his career.

Despite ending up on the wrong end of the result, Matchroom promoter Hearn was full of praise for his star, drawing attention to his never-say-die attitude in the ring.

"It was the first round, after that he was fighting on heart and desire," Hearn said. "I'm so proud because he never gave up, his legs were deceiving him and he kept on trying.

"When you are in there with a massive puncher this is what can happen. He never stopped trying to get up, even when he couldn't get up at the end."

Hearn was also quick to fete rival Dubois in his first IBF title defence, adding: "Daniel deserves credit, he's a real world champion. Congratulations to him."

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