Yet today his feet remain firmly planted on Planet Earth, with the coveted Lonsdale belt taking pride of place in his Halesowen home.
Clarke’s stunning knockout of Willy Hutchinson – the man whose pre-fight prediction proved as inaccurate as his punches – in front of the BT Sport cameras on Saturday night did not so much upset the applecart as totally demolish it.
From rank outsider, not least with bookmakers who had him priced at 16-1 to win by stoppage, Clarke now finds himself a major player in the super-middleweight division.
“Pretty much everyone had written me off, so they can have that,” he chuckles. “I know I am a British level fighter and more. All I needed was a chance and once it came along, I wasn’t going to be denied.”
Moments like Saturday do not happen by luck. For Clarke, it was the culmination of countless hours of unseen work in the gym, together with years of maintaining head and heart through a professional career spent chiefly, until now, on the small hall circuit patiently waiting for the big opportunity to arrive.
Along the way there have been ups and downs, injuries to overcome and an ongoing battle with the lung disease sarcoidosis.
In December 2019 it looked like the moment might have passed him by when, having been handed a shot at the British title, he lost to Lerrone Richards on a split decision.
His first and still only defeat in the pro ranks, Clarke had been hindered by a shoulder injury which left him unable to throw his right hand for the duration of the fight. On Saturday, somewhat fittingly, it was those punches which first stunned Hutchinson and then sent him crashing to the canvas in the fifth round.
“I probably shouldn’t have boxed against Richards,” says Clarke. “Two hours before that fight I was in the surgeon’s room having treatment.
“You seem like a sore loser saying you were injured but I have always thrown my heaviest shots with the right so to be without it that night was a major disadvantage and it took months of rehab to get it right again. I think Saturday showed just how effective it is.
“All people ever see is the end product. They never see the training, the weeks of being constantly tired, craving the food you know you can’t have. It’s all worth it in the end.”
Victory over Hutchinson, a former European amateur champion touted in some quarters as “the next Joe Calzaghe” after winning nine of his first 13 pro fights by knockout, was also the latest notable success for Black Country Boxing, the Wednesbury-based gym and promotions company starting to make an increasing mark on the sport.
Though the pandemic has made things financially tough for boxing’s smaller players, it has also presented opportunities for the likes of BCB and their fight-ready stable.
Super flyweight Ijaz Ahmed, who like Clarke trains in Wednesbury, became a European champion in late February, while Kingswinford welterweight Danny Ball retained his WBC international silver on the undercard of the Clarke-Hutchinson bout.
The previous night had seen Derby’s Zach Parker, also managed by BCB, extend his record to 20-0 with an impressive second-round stoppage of American Vaughn Alexander.
“Boxing is all about momentum. At this moment we are on a bit of a roll and we have to try and keep that going,” says BCB’s head of boxing Errol Johnson, who quit his long-time job with Sandwell council to found the company four years ago this month together with head coach Paul Mann and Walsall FC director Dan Mole, who heads up their PR.
Described by colleagues as a “walking encyclopedia of boxing”, Johnson has done pretty much every role imaginable in the sport and has been training fighters for more than three decades.
His influence on Clarke, who had just six white collar fights before turning pro in 2013, has been considerable.
“Errol is like my boxing dad,” smiles Clarke. “He is the main man. I have been with him from the start and I will be with him until the end. He deserves all the success he gets.”
Johnson has never been one to seek the limelight or boast about his achievements during a career which has previously seen him guide the likes of Young Mutley, Martin Gethin and Jason Welborn to title glory.
Yet BCB have big ambitions and are set to expand further later this month with the opening of an amateur gym.
Johnson’s long-term aim, meanwhile, is to bring a world title belt back to Wednesbury. Clarke, who can look forward to more time in front of the BT Sport cameras after signing with Frank Warren’s Queensberry promotions, might just be the man to deliver it.
“You have to aim for world titles,” says Johnson. “Lennox wants to move up but is tricky right now with the pandemic still limiting the sport.
“Perhaps we will look at one or two defences of the British belt to keep him moving up.
“There are always possibilities and we’ve always said we will box anyone. Len will always be in good fights.
“The long-term aim has to be to have a world champion in the camp. We just want to keep bringing new talent through and hopefully push on from what we have won over the last six months.
“Now we have a few fighters involved with the bigger promoters, but you have to keep winning. Boxing is one of those games, it can soon switch. But right now, things are really good.”