TYSON FURY ‘struggled to run three miles’ just weeks before battering Deontay Wilder, his dad John revealed.
The Gypsy King smashed up the Bronze Bomber for 11 rounds before eventually securing a knockout.
But John Fury suggested his son was well behind on his fitness in the run up to fight night.
The family endured the emotional turmoil of Tyson’s sixth child, Athena, going into intensive care when she was born in August, kept in at Alder Hey Hospital in Liverpool.
His father told Sky Sports: “I went to Alder Hey Hospital, I accompanied him just to keep him right.
“I said, ‘Look, you’ve got to do some form of exercise, just don’t sit in here. Let’s go for a bit of a run, you’ll feel better after it.’
“I’m 56 years old, 20 stone, I outran him. We went for a run around Liverpool and his lungs were on fire.
“I thought, ‘Look at this.’ My lungs? You couldn’t hear them. He struggled with a three-mile run.
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“He said afterwards, ‘That nearly killed me’, so that’s where he was at four weeks prior to that big night.”
And by Saturday night, he was ready to take on his rival for a third time.
Fury dropped Wilder in the third but hit the canvas himself twice in the next round – but eventually stopped the fight in the 11th to maintain his unbeaten record and keep the WBC heavyweight world title.
Fury Sr revealed how he kept his son motivated in the final stages of preparation – including using Anthony Joshua’s defeat at the Tottenham Hotspur Stadium against Oleksandr Usyk to fire Tyson up.
He added: “He was going to do it anyway, so what I said was, ‘OK then, I’ll try to make the best of a bad job. I’ll fill him full of confidence.’
“But deep down inside I was worried because I thought ‘You know what, he shouldn’t be doing this.’
“There’s a power to be in boxing, Tyson wanting to stand up for his country knowing Anthony Joshua just lost his belts at home, two miles from where he lives.
“He thought, ‘You know what, I can’t be like this man, I’ve got to do my own thing, stand for my country. Win, lose or draw it’s on!”