Discussing his career to date and his aims for the future, he is at pains to emphasise the importance of taking each fight as it comes, of taking the advice of his corner, of following the game plan.
But scratch the surface a little, and his constant desire to improve, to become the best he can be, is unshakeable.
Speaking exclusively to The Sport Review, Campbell said: “When I lose that fighting spirit of me wanting to be better than myself all the time, then I know that it’s time for me to get out of this sport.
“It’s a hard enough sport as it is; if I haven’t got that passion to be better than I was yesterday and to continue to want to win and to be the best I can, then I think it’s time to get out.”
In the meantime, though, would he be unhappy if he wasn’t a world champion within the next five years? “Of course.”
The Hull southpaw – inevitably nicknamed ‘Cool Hand’ – was speaking ahead of his eighth professional fight, against Polish veteran Krzyzstof Szot on the George Groves undercard at Wembley this Saturday.
Campbell comes into the ring with a perfect pro record to date, his seven victories including five inside the distance; and after Scot, he faces Argentine Daniel Brizuela for the vacant WBA Inter-Continental Lightweight belt – his first title bout, and first 12-round fight – at the Ice Arena in Hull on 25 October.
And he is sounding confident.
“Training’s been going really well. I know everybody says that, but it’s been going as good as it can go. I’m looking forward to getting out there and boxing Saturday night.”
Nothing will get in his way. He turns 27 on 27 September, but that is “right in the middle of a training camp” for the Brizuela bout, and so significant celebrations will be deferred – he will “maybe have a real celebration after the show in October in Hull”.
Campbell is the sort of man who is reluctant to look too far ahead; but there is only one name on the lips of British boxing fans for his prospects in 2015.
Fellow Hull native Tommy Coyle faces Michael Katsidis on the same bill as Campbell-Brizuela. Two years younger than Campbell, but with four years more experience on the pro circuit, the prospect of a match-up next summer at Hull City’s KC Stadium is clearly an enticing one.
“There’s a lot of people that are excited about the chance of that coming off in Hull, and if that fight does come off, I’m happy to take that and put on a massive show. If the people want to see it, then I want to give it. That potentially, next summer, could be a massive event. Outdoors, at the KC stadium, it would be a fantastic night for everybody.”
We touch on London 2012, where Campbell was part of a British boxing gold rush. He acknowledges that, in some respects, his bantamweight gold medal will be difficult to top.
“It’s definitely the pinnacle of my career.”
Admitting that he cannot resist looking at his gold post box, which sits proudly on Hessle Road in Hull near a similarly lustrous phone box in Market Place, he says of his Olympic triumph: “It will live with me, will be in my body and my heart for ever, and it will be for my friends and family as well.”
But when asked about the memories he has taken with him from London, there is a real niggle under the surface.
“The fight against [Bulgarian Detelin Dalakliev, in the quarter-final], when they were cheating me for two rounds, and were scoring against me, and I was winning the fight and they weren’t giving me it. But I dug deep, giving everything I had, and ended up winning the fight by one point [16-15, having been 8-9 down with one round to go].”
Would anything have changed if that result had gone against him? “I could have retired from boxing full stop if I didn’t get that result. Who knows what paths I would have taken? I know I won the fight a lot easier than the points score.”
In the end, though, Campbell took gold, beating Ireland’s John Joe Nevin 14-11 in the final, and took the decision to turn professional in 2013.
He admits that he has a definite fondness for his amateur career – “winning the tournament glories and bringing home gold medals, I do miss that part of things” – but says that he felt that he had won everything that he could, and wanted to take on new challenges.
And things have changed since he turned professional.
“There is a difference. I’m still going through all that learning stage now. I still do a few things a bit amateur-y, but I’m adapting. I’m learning all the time.”
Such as? “Sitting down more on shots – you’re not point-picking any more.”
He expands on the tactical differences between the professional and amateur circuits: “You’re fighting 12 rounds and not three, so you can’t rush your work.”
But it also comes down to the fans: “It’s an entertainment sport. People like to see good, entertaining fights.”
Campbell speaks of the lessons he has learned from more experienced boxers, saving particular praise for Carl Froch, whom he spoke to during the Olympics about dealing with pressure. He talks of the ‘game face’: “You don’t show emotions.”
But there has been an emotional edge this year. Campbell took some time out of the sport in April after his father, Bernard, was diagnosed with cancer, and it is clear that Bernard has been a huge influence on his career.
“He’s my inspiration to continue with my fighting spirit. Nothing gets him down, nothing’s going to beat him.”
Campbell admits that it was difficult initially to digest what was going on, but says that he has drawn strength from watching his father’s battle against the disease.
“My dad’s the strongest person I’ve ever met. He will overcome anything, and just to see that from him just gives me so much fighting spirit. When the bell goes, I feel as though I’m a tough, tough fighter and I can get through a lot of things and overcome a lot of things. And that’s due to my father.”
Before we wrap up – Campbell is heading to the launch of Manhattan Loft Gardens, a new apartment, hotel and sky garden development in London’s Stratford City – we touch on his fledgling television career.
Campbell finished third in Dancing on Ice in 2013, and has recently appeared on A Question of Sport and All Star Mr and Mrs. Can we, maybe, expect to see him rebuilding the reputation of boxers on Strictly Come Dancing?
“If I was ever to do a show like that, it would be at the end of my career, because of the time consumed and what it takes.” But not ruling it out for the future? “Definitely not ruling it out for the future.”
But for now, he is back fighting, just like his dad.
Luke is supporting Cancer Research UK’s new campaign #WeWill beat cancer sooner. Join the fight at cruk.org
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