It is often said that boxing is as much a mental sport as it is a physical one.

Daniel Dubois’ athletic abilities have never been in question but there have been doubts as to whether he possesses the mental strength required to become a true, top level heavyweight. 

Having succumbed to defeat against Joe Joyce and Oleksandr Usyk, Dubois’ reputation as one of the heavyweight division’s most explosive hopes was in severe danger of being overshadowed by the belief that he was an on-top fighter who quits when things get too tough.

Last December, rather than handling him with kid gloves, Dubois’ promoter, Frank Warren, matched him with controversial but ambitious American, Jarrell Miller, and dubbed the fight a “make or break” night for the 26-year-old. 

As the most pivotal night of his career approached, the reserved Dubois found himself directly in the crosshairs of one of boxing’s most prolific trash-talkers. 

Dubois came of age. He carried himself with confidence, came out of himself during some amusing pre-fight press conferences and, on fight night, he bowed but refused to break, fighting through fatigue and self-doubt to accelerate through the gears and stop “Big Baby” in the final round.

It was a massive step in the right direction but Dubois faces a different – more menacing – test of character this weekend.

Miller is a big, loud presence but throughout the build-up to the fight, Dubois will have been able to fall back on the knowledge that he was in charge of his own destiny and that as long as he prepared properly, boxed sensibly and showed resilience, it was always likely that he would eventually have too much natural ability for the New Yorker.

Filip Hrgovic presents an altogether different proposition in Riyadh on Saturday.

Dubois will need to take his game to a different level if he is to beat the confident and unbeaten Croatian. Hrgovic also has taken every opportunity to remind the Londoner of some – apparently – one sided sparring sessions that took place when Dubois was still a teenager.

Boxers need to have short memories when it comes to the worry of defeat or pain but there will undoubtedly be fleeting moments between now and Saturday’s fight where Dubois will get flashbacks of those sparring sessions or begin to question himself. The ability to overcome self-doubt is an important part of any successful boxer’s make-up but there is the sense that it is absolutely crucial that Dubois gets off to a good start if he is to beat Hrgovic. 

“Frank’s always believed in me. He knows I can do it. It’s just about me knowing I can do it and going out there and showing it,” Dubois told Queensberry. “I know what I’ve got and I’m gonna use it. That [Miller] was a really important fight for me, that hurdle. I’ve done that and on to the next one. I’m giving myself goals and every fight I’ve got to get better. I’ll put in a better performance this time.”

Dubois clearly senses that this isn’t the time for knockabout quips and light-hearted pre-fight exchanges. If beating Miller saved his career, getting past Hrgovic would take it to an entirely different level.

“For different fighters it changes,” he said. “It’s who you’ve got in front of you. Jarrell sold the fight well. It was what it was. This one, I think it’s gotta be plain and simple. It’s not complicated with this guy. I’ve prepared in the gym. I’ve sharpened my tools up and I’m ready to go out there and do it. “

Dubois’ trainer, Don Charles, has been working with Dubois since last May and has slowly begun to work out what makes him tick. Charles – who worked with another mercurial heavyweight, Dereck Chisora, for years – put together the plan to beat Miller but also acted as motivator and cheerleader in the corner, helping to guide his fighter through those tricky middle rounds.

Charles insists that Dubois’s improved mental strength is just part of him growing as a man and a fighter. 

“We’re always the underdog. In my belief, overdog, underdog, sidedog, it doesn’t matter. It’s a fight. We always train to win and we always come to win and that’s what we’ve come here for,” Charles said this week.

“It’s called development. It’s called maturity. It’s called evolution. All of those words combined to one. He had to do it himself and find himself. It’s him who’s in that ring. He’s got a lot of wonderful people around him with his family and the team and it’s a collective effort to get him where he is now.”

One of those people is Kieran Farrell. The Mancunian has forged a successful career as a trainer, manager and promoter since being forced to retire from the sport after suffered serious injuries during his fight with Anthony Crolla back in 2012. Farrell is a lively, busy character who is known for his fast pad work.

Charles doesn’t want to give away his strategy but with Farrell on board, Dubois mentioning “sharpening his tools” and Charles’ belief that the fight will end by knockout, the signs are pointing to Dubois being aggressive and looking for that all important fast start.

“There are a number of keys and things we have to do to win. I’m not gonna give the gameplan but the key to victory is to follow the gameplan as closely as possible to how we’ve trained,” he said.

“It’ll be a stoppage. We’re gonna be the judge and the jury, basically.”