Anthony Joshua vs Dillian Whyte: Joshua in a fight to restore the good name of boxing, writes Steve Bunce

Both Dillian Whyte and Anthony Joshua have heard the sirens coming, have fought their way from tiny squabbles above pubs to what passes for boxing redemption on Saturday night in an illuminated ring at the centre of the latest pay-per-view offering.

Joshua and Whyte met before at the Boston Dome, a giant Irish pub at the centre of a dwindling Irish community in Tufnell Park, north London, one day in 2009. Whyte was fighting for the first time, Joshua for the fifth and at the end of three rounds, after Joshua had touched down, Whyte’s hand was raised.

“It means nothing,” Joshua said this week and that is possibly true, but tomorrow’s British heavyweight title fight at the O2 means everything and not just for the slickly packaged, protected and immensely likeable Joshua. In a week when Tyson Fury was knocked from the top of the list of hate by the faded playboy, political crank and former boxing promoter Donald Trump, it has been left to Joshua to lift the sport’s spirits. It is a hefty job, even for the saint-like Joshua.

Back in 2012 Joshua survived a torrid fortnight at the Olympic boxing event, emerging after four contests with the gold medal and scraping home by the narrowest of margins in two of his outings. In the Olympic ring Joshua made his luck, as we say in boxing, by refusing to back down and not accepting the odds stacked against him in fights with professional veterans from Cuba and Italy.

“I knew that it was my turn to do something, to prove to people that I could be somebody,” said Joshua. “In the final, with one round to go, I said to myself: ‘You have one round to change your life’. It meant that much.”

Joshua has been a model citizen since then and that is part of what has upset Whyte, a man portrayed as the outcast in this fight, a boxer from the distant side of boxing’s filthy tracks: he trains in a railway arch in Brixton where buckets collect the rainwater. Whyte has been a street guy and Joshua, a man comfortable on the same corners over the years, has morphed into a muscle-bound Eliza Doolittle, surrounded by born-again Christians, a devoted flock of city boys and slick hucksters in convertible Bentleys.

A year ago Whyte returned after a drugs ban – it was an over-the-counter recovery drink – and was fighting for peanuts in venues like the Camden Centre at King’s Cross. Joshua, and his people at that time, had done everything possible to erase the dirty memory of the amateur loss as they guided him on their red-carpet ride. Whyte was ignored, insulted in many ways, and tucked away.

I agree with Joshua when he says the fight at the Boston means very little, but without that grainy footage, without that fight there would be no showdown, no sold-out venue and no riches for either fighter tomorrow.

It is impossible to dislike either Joshua or Whyte as men or boxers. However, the pair of them could so easily have been so far from tomorrow's main attraction that it adds a dimension of fantasy to the proceedings. They have each stood at the edge, peering over into a hateful lifestyle and they each at some dark midnight moment turned away. Tomorrow’s fight has made the old ugliness surface, the anger is back and that is what makes this so special.

It is possible that Whyte’s exile and his much harder lifestyle will be brutally exposed once the bell sounds. Joshua has been on big stages, has won the gold against form, has been pampered and not had to sweat in vain during three years of his pro career. Joshua has been in Wladimir Klitschko’s training camps in the Austrian Alps and the fallen world champion declared the boxer the future of the sport. Whyte went unnoticed in the same camps, just another sparring partner collecting good pay.

It was at a camp last year that the pair sat down – a fighter called Kevin Johnson slyly arranging the peace talks – to clear the savage air. The hate was thick and potentially violent. “We both agreed to hold it back, be cool and one day we would fight again,” remembers Whyte.

Whyte is 27 and unbeaten in 16 fights, Joshua 26 and unbeaten in 14 fights. Whyte has watched his weight go up and down, has had to schlep all over Britain to get sparring and lived in a caravan with the Fury clan for a time. “They were good people, proper people,” Whyte insists.

Joshua has been in a cocoon since agreeing terms to fight professionally. He divides his time between the luxuries of the Matchroom gym in Essex and his old haunt in Sheffield, where he trained for the Olympics with the GB boxing coach, Robert McCracken. In Sheffield, where the GB squad is currently preparing for a crucial six months of Olympic qualifiers (so far not one boxer from Britain has secured a place in Rio), Joshua can relax. He might seem a bit cosmetic at times, but don’t imagine that makes him fake in any way.

Tomorrow's fight will be the end of the comfort zone for Joshua, even if Whyte is bowled over in 60 seconds and especially if his sense deserts him and he goes toe-to-toe with his opponent in an honest brawl the sport deserves. The crucial learning curve for a fighter in any fight is not measured by time: a fighter learns through pressure, by not making mistakes, and through concentrating when a big fight starts. This is a big fight and the British heavyweight championship is just a fitting bauble attached to the victory jig of the winner.