Now the challenger, Joshua saw that Usyk, the IBF, WBO and WBA heavyweight champion, has bulked up for this second fight.

But Joshua warned the Ukrainian that it won't be enough. "If you're a puncher, punchers aren't made, they're born," he told Sky Sports News.

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"Bulking up, it's probably to help you absorb more punishment," he continued. "Lifting weights and all that doesn't really make you a puncher. But it may help you absorb more punishment."

If Usyk's gruelling preparations have made him a more formidable opponent, Joshua welcomes the challenge.

"I can't speak on what his gameplan is or why he's done it. They know why. I want it to work for him because I want a good fight. I want to put on a good show," he insisted.

Usyk brought an element of mischief to Wednesday's press conference at the Shangri La hotel in Jeddah. He made Joshua wait for his arrival, scribbled notes as the other participants spoke and made sure he had the final word.

But Joshua denied there was any element of mind games. "No, not at all," he said. "It is what it is. If you are into body language and psychology then you can read into it. But that's not really my forte. My forte's boxing and on Saturday that's where I've got to do my studying.

"I don't really take too much from a press conference, it is what it is. You say what you want to say and you do your best on Saturday night. That's what I'm focused on."

His motivation for this rematch, a fight that will be crucial for the future direction of his career, can't be doubted.

"I feel like the competitive spirit has risen up," he said. "This time, I don't care, I just want to win. Whatever it takes.

"So that might mean exerting more energy, more punch combinations so your mindset changes towards what your goals are. So this time my goal is just about competing, winning."

Nor is he forecasting an early night. "That's why bookies are there, for predictions. But for me I'm thinking 12-round war," he declared.

"A 12-round war, anything short of that is a bonus."

'I get my motivation from my people'

The champion came to the last media event before Friday's weigh in dressed in traditional Ukrainian clothing, the outfit of a Cossack warrior.

After facing off with Joshua, he burst into song that his team wholeheartedly joined in with. They sang "Oi u luzi chervona kalyna", an 1875 call to arms inspired by Ukraine's 18th-century battle for independence, sung now in a display of defiance in the face of Russia's invasion.

Usyk served as a military volunteer in Kiev before electing to represent his homeland in this global event. He remains inspired by the struggle in Ukraine.

"I get my motivation from my people, from my country, from my family, from the Lord, from my faith," he told Sky Sports News.

He expanded too on the essence of competition that is fuelling him for this fight. "The sun goes up, we get up. The deer is running and the tiger is chasing it. If it wants to live, it has to run away from the tiger. If he wants to live he has to catch it to eat," Usyk said.

"The one who does not compete, does not live."

If that parable is anything to go by, Usyk intends to compete ferociously hard on Saturday night.

Anthony Joshua's huge heavyweight rematch against Oleksandr Usyk is on Saturday August 20, live on Sky Sports Box Office. Book Usyk vs Joshua 2 now!