She has trained hard, gone through heavy, physical sparring sessions and more. But even then Marshall wasn't ready for the American's unique approach to their head-to-head filming of The Gloves Are Off.

"There was every emotion going in that. There was singing. There were tears, there was a bit of defence. There was a bit of gratefulness," Marshall told Sky Sports afterwards. "Weird."

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Crews-Dezurn didn't close out with the kind of trash-talking typically seen in boxing. Instead she memorably burst into song, in celebration of her own championship status.

The American is a unique character in boxing. Crews-Dezurn also left no doubt that she has every intention of finishing their fight in Manchester still in possession of her four title belts.

She told Marshall directly: "Savannah's a pit stop for me. Respectfully, disrespectfully. My mission is so much bigger. And if I got to walk through you, walk through hell, the UK fans, to make my heaven, it's going to happen."

Crew-Dezurn also condemned Marshall for failing to take responsibility for her loss to Claressa Shields.

"Boxing is not a team sport. You have support from your coaches. Yes, your training partner's beside you, but when it's you and I in the ring, or you and whoever in the ring, it's just you two," the American said.

"When you when you lose, you could throw the blame. When I lose, they throw me away."

Reacting to Crews-Dezurn's claim she'd be 'easy work', Marshall said: "That's a lie."

The Briton is determined to be a champion again. "I want it more than ever," she said. "I'm craving it.

"I can't walk away after that loss. I can't walk away with nothing. I want the belts. I want to be known as a champion."

Franchon Crews-Dezurn vs Savannah Marshall: The Gloves are Off is released on Sunday