Day, 27, from Freeport, New York, was instantly knocked out and it wasn’t clear if he regained consciousness. He was treated by a doctor in the ring and then was rushed off on a stretcher by paramedics and transported to the hospital.
There was no immediate word on his condition.
Day was knocked down twice earlier in the fight.
Eddie Hearn, the managing director of the promoter, Matchroom Sport, said only he “didn’t think the situation is great.”
Hearn said he felt Day’s family and manager, Lou DiBella, would want to make their own statement.
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