Josh Kelly is on a good run. He’s won every fight he’s had since his punishing 2021 loss to David Avanesyan, including an impressive British title victory over Troy Williamson.

But the questions raised by the Avanesyan defeat have haunted Kelly ever since. He intends to answer them once and for all when he fights Liam Smith on September 21.

Kelly and Smith box on the Anthony Joshua vs Daniel Dubois undercard at Wembley Stadium, live on Sky Sports Box Office.

Smith is a former super-welterweight world champion who’s fought Canelo Alvarez and a plethora of top fighters, most recently exchanging a win and a loss with Chris Eubank Jr.

He is a master at applying aggressive pressure, and if Kelly hasn’t ironed flaws out of his boxing, Smith will expose them.

Kelly’s trainer Adam Booth, however, is convinced his fighter is now ready for this test.

“Josh is in his prime. The last two-and-a-half years have really been the most important progression mentally. He’s learned a lot about himself and recovered a lot of problems that he’s had for years,” Booth told Sky Sports.

“Ever since the first day he walked into my gym six-and-a-half years ago and he sparred Billy Joe Saunders, Andy Lee, Liam Williams, he proved then that he had the grade in him. It was just his mind and his mindset and his maturity and understanding of himself that needed to catch up.

“It did with the work that he’s been doing. But now he is in his prime and I will genuinely match him against anyone.”

Kelly has never boxed higher than super-welter, while Smith’s last three fights have been at middleweight. But Booth insists Kelly won’t be at a significant disadvantage in size and strength.

“Josh is a very big 154lbs, and Liam is a 154 who’s just a bit older now. He’s tough, experienced and rough enough to be a 160lbs fighter but the difference between 154 and 160 isn’t that much,” Booth said.

“I expect, knowing Liam and knowing Josh, that the difference when they’re in the ring will be about two pounds at most. It’s an even match up and I think people will be surprised when the fight starts Josh will be the one that looks bigger.”

Kelly is regarded as a gifted stylist, rather than a destructive force. But he might be able to change that perception in this fight.

“You’re going to see much more,” Booth promised. “You won’t see the same because the Troy [Williamson] fight was actually still part of his rehabilitation or evolution and understanding of himself and getting life into perspective.

“If you look at the Troy fight it was a movement and defensive masterclass. But he’s much more dangerous than that now. If you go back and you look at the footage of Josh and you look at him now physically there’s an immense difference since December 2022 and that’s probably what excites me the most.

“I know he can be hurtful. I know he’s a lot tougher and a lot stronger than people realise, because of the style that he boxes.

“But also since the Troy fight, the bite that he’s been getting on his shots in the gym and in the ring now is starting to show out and I think that September 21 will just be more of a progression.

“He still won’t be the completed article, I think there’s still more to come from him. But at this stage and where he’s at, I’m genuinely excited about how he boxes and how he’s going about day-to-day life, and how well he’s landing shots now.”

Kelly’s results, so far, have not matched the expectations for him. But Booth has not lost faith that his charge is a special fighter.

“You know unique talent when you see it and whether that talent can fulfil its potential,” he said.

“When a talent like Josh Kelly does fulfil its potential, it does go to the highest level.”

Watch Anthony Joshua vs Daniel Dubois at Wembley Stadium live on Sky Sports Box Office on September 21.