EXAMPLES of the transformative power of sport walk into Peter Harrison’s gym off the street every day. Kids who are being bullied at school can find self-confidence there; others who are finding themselves in trouble can discover a more positive outlet for their pent-up aggression.

But perhaps the biggest and best example of this is his own son Scott, who walked back into his eponymous school of boxing at the Phoenix ABC gym in Dalmarnock in July after serving three years of his four-year jail term for assault in first Malaga then Barlinnie.

While the stretch saw him rediscover a latent talent for art by painting portraits such as Rangers and Celtic managers Steven Gerrard and Brendan Rodgers, his first love was always boxing and the canvas where he has produced his best works of art will always be the boxing ring.

While the former world champion, now 41, will return to competitive action under the auspices of the British and Irish Boxing Authority when he takes on Tackie Annan of Ghana in Glasgow on Saturday, that is why Peter can’t believe the British Boxing Board of Control (BBBoC) still want to deprive his son the chance to do it for a living.

“I don’t know what it is with the BBBoC, or what they think he is,” said Peter, who trained his son. "Scott is a good father, a good son, and a good boxer. He is a professional athlete at the end of the day. He is not just fit, he is super fit."

While he always held out hope, there were times on this journey where Peter wasn't sure that a day like Saturday would ever come. Scott's extradition case was a drawn-out and demoralising affair for all concerned.

“I am so glad Scott is back because it is so hard when you know your son has been treated badly,” Peter said. “What happened to him out in Spain, spending time in a Spanish jail then back here too. I don’t want to talk about what happened to him over there."

While the licence issue could preclude him taking on the biggest nights, don't bet against him having a belt around his waist sooner rather than later.

“Scott has always won titles, from a very young age," his father said. "At 16, he won a European amateur medal, but instead of going to the Olympic Games he turned professional. He is an artist, a brilliant painter. And a boxer, he is not bad at that as well! So I am glad he is back into his boxing.

“People don’t realise what sport does to people. I get a lot of young people up here at the club at night, and the parents are quite happy. They could be in trouble at school, trouble here, trouble there, then all of a sudden they change. Maybe we have a couple of people who are being bullied and it just changes completely.

“There was nothing, no medical reason why they [the BBBoC] didn’t want him to box. It was just because it was Scott Harrison, and he had been fighting in a pub in Spain. Is he not supposed to keep his hands up and defend himself?”

Harrison’s career spiralled into alcohol use and violence, but few fighters push themselves harder in preparation for their bouts. Famed for punishing training runs up Ben Nevis in preparation for his bouts, he now gets his hill runs in up Cathkin Braes, with Peter in the car in front, clearing the way. An occasional victim of "tall poppy syndrome" when out and about in Glasgow, he has been overwhelmed by the positive response since his release.

“Scott was brought up well but Glasgow is a goldfish bowl and sometimes people tried to make trouble for him,” said Peter. “When Scott first came back in here, I’m sure some younger folk were thinking ‘why is that guy in here’. But anybody who has seen Scott box, and where Scott has boxed – Madison Square Garden – knows what he is all about.

“His training is never something easy, it is always something hard. We used to go up to Fort William, now he is up Cathkin Braes. That is where Benny Lynch used to go too.”