Many are calling the Anthony Joshua/Wladimir Klitschko bout Britain's biggest ever, with a record 90,000 sold-out crowd ready to pack Wembley Stadium come fight night on 29 April.
Officially Joshua is defending his IBF title, and hoping to annex the WBA and IBO titles too. But he will earn more than just alphabet honours should he take Klitschko down.
The two fighters are almost identical in size, they're both massive and muscular, but the difference is in experience and age. Joshua has had only 18 professional fights - that's the number of times Klitschko defended his world title.
Klitschko had reigned as heavyweight champion for over 11 years before losing his title to Tyson Fury, another Brit. It was one of the Ukrainian's poorest performances, and with Fury vacating his WBO and WBA titles for personal reasons, Klitschko was unable to avenge the defeat.
While Klitschko might be looking in the rear-view mirror, Joshua has the world ahead of him. He's 27 and keen to conquer America: "The United States is the mecca of boxing and we're trying to build an American audience, a bit like Hatton, Lewis and Hamed managed to do," he said, referring to British boxers Ricky Hatton, Lennox Lewis, and 'Prince' Naseem Hamed.
Joshua, born in England, is of Nigerian heritage and spent some of his childhood there before returning to England in his teens. His full name is Anthony Oluwafemi Olaseni Joshua.
In talking about his youth, he admitted: "It was all about how I looked, my clothes, clubbing, girls. I wasn't with the best group of people."
But things turned around dramatically when he joined a boxing gym. His sheer size (1.98m and 108kg) and speed (he runs a very fast 100 metres) caught the eye of the coaches and soon he was training day and night. But in 2010 he faced one of those crossroads moments at the heart of all coming-of-age stories. The police caught him in possession of cannabis. Happily for British and Nigerian boxing fans he took the high road.
"The arrest changed a lot. It forced me to grow up and accept my responsibilities," Joshua admits. "It wasn't so much the actual charge that had the effect. It was all the grief afterwards, from my friends, from my family - especially my mum - and from my boxing."
Two years later he won gold at the London Olympics and soon after went professional, fighting opponents who must have wished that he'd taken the low road. Two of them were knocked out in the seventh round, the rest were all stopped within three.
Joshua has the looks and the personality to become the Tiger Woods of boxing, but there's a very big and skilled Ukrainian standing in his way. For his part, Klitschko will want to prove that his loss to Fury was an aberration, that he's still the undisputed champ. He knows he won't have another opportunity to beat Joshua: "Some say this fight is too late for me, too soon for him, but it's perfect. In three years I will be too old and he will be too good, so the timing is perfect."