Mark Prince had a far more compelling reason.

Before his initial retirement with a knee injury 18 years ago, Tottenham's Prince had an impressive career as a light-heavyweight, holding both the International Boxing Federation (IBF) and World Boxing Organisation (WBO) Inter-Continental titles and fighting for a World Championship in what was to be his only defeat in 21 bouts. 

That was back in 1998.

His life was to change dramatically eight years later on the afternoon of Thursday May 18 in 2006, when his 15-year-old son, Kiyan, a prodigiously talented young footballer on the books of Queens Park Rangers, was brutally murdered outside the gates of his school in Edgware, North London, the innocent victim of a knife crime for which his attacker, aged 16, was jailed for life.

His distraught father was instrumental, along with the then Mayor of London, Ken Livingstone, in lobbying for knife crime to be introduced into the Violent Crime Reduction Act. He also set up a charitable foundation in memory of his son with the aim of campaigning in schools, prisons and the community, as well as counselling bereaved families similar to his. And there have been many in recent years. Far too many.

Prince resumed his career after 15 years with a ring return which he hoped would raise both the profile of the Kiyan Prince Foundation and much-needed money for it.

On October 10 in 2013 he stepped back into the ring at London's York Hall against Czech cruiserweight Jindrich Velecky, a prelude, he hoped, to another world-title shot, driven by the desire to keep alive the memory of his son and highlight the horror of what happened to him, and others.

But his world title aspiration was not to be. 

Prince won this fight, and three more over the next two years, but, as he reveals in his newly-published biography "the thought of killing myself in training didn’t appeal to me and I needed to be dedicated 100 per cent to the Kiyan Prince Foundation".

He adds: "After a comeback trail of four fights, three stoppages and no losses, I decided it was time to hang up the gloves for good and concentrate on the real battle that lay outside of the ring."

And what a battle that has been with the escalating surge in violent crime across the United Kingdom.

In London at least 36 people have been fatally stabbed since the beginning of the year, making the capital one of the deadliest in the world.

Metropolitan Police records show 37,443 recorded knife offences and 6,694 recorded gun offences across the UK in the year up to September 2017.

In London, the problem was even more pronounced than the rest of the country, with 12,980 knife crimes taking place in the capital - 2,452 more than the equivalent year.

Four teenagers were stabbed to death in London on New Year's Eve alone, and 22 were killed in March - meaning the capital now has a higher murder rate than New York City.

Knife crime across the country has risen by a staggering 21 per cent in the 12 months to September 2017, according to quarterly figures released by the Office of National Statistics.

Stabbings in London are at their highest level in six years, with a 23 per cent rise from the previous year.

Now, even boxing clubs, traditionally a refuge for wayward kids, admit they are losing the battle to lure them off the streets. One club coach in Hackney, East London - heartland of the 2012 Olympic Games - asks: "When young lads can earn £500 or so a week selling drugs what attraction is boxing or any other sport?"

And so many if these kids seem to be involved in knife crime of the sort that took the life of Kiyan Prince a dozen years ago.

Mark’s book The Prince of Peace - published this month by Trinity Mirror Sports Media at £12.99 - is not only a compelling, poignant and emotive account of his battles in the ring, his selfless pursuit against knife crime and the effect his son’s death had on him and his family, but a timely reminder of the violent times in which we live.

It also happens to coincide with the 25th anniversary of the fatal stabbing of Stephen Lawrence, knifed to death by a gang of white youths as he waited at a bus stop in Eltham, South East London, simply because he was black.

It was a crime which shocked the nation, laying bare the racism in society and more specifically the police.

It took 19 years, until 2012, when only two of the five thugs involved in the attack were convicted and jailed for life.

At least justice came more swiftly in the case of Kiyan Prince.

Kiyan died from a stab wound to the heart after going to help a friend who was being bullied, and trying to break up the fight. He was wearing his QPR shorts and other friends said later that he was jumped on as he walked away, and that his last words were: "Please don't let me die... tell my mum I love her."

"I was so proud of him," says Prince. "We had just been down to the QPR ground. They wanted to sign him as a pro and talked of what a great future he had. They said he was the next Theo Walcott. He was growing into a fine young man, quiet and shy but full of character."

The boy who stabbed Kiyan, Hannad Hassan, a Somali refugee, was said to be obsessed with gang culture. He received a life sentence, but Prince objects: "My boy was 15-years-old. His killer will spend less than that in prison. That's not life.

"Boxing helped me get through every day after Kiyan was killed. At the time I didn't think I could survive. I was sure I was going to do something crazy to get revenge, because there was hatred in my heart.

"But I asked God for help and saw I had to do things a different way. That was to share my experience with others. I went into the streets and the schools and prisons. I spoke with gang members and told them of the hurt they were causing. I like to think I opened some eyes. Some seemed to look up to me because I was a boxer. Some even swore never to carry knives or guns again."

Now, he says, the Foundation must be kept in the spotlight, and the publication of his story is the latest part of it. "I hope I can help spread the message and make street crime unfashionable, and say to them, 'You know, this ain't cool'. Some kids see carrying knives as a badge of honour, but I tell them it's one only a fool would wear."

Ex-boxer Prince continues his mission to save young lives despite the staggering statistics in the opposite corner. "This mission has to be completed, it is about promoting this charity and helping kids to come and work through our projects and programmes and be changed into new and different young people. People like Kiyan."