Williamson, 34, capped a remarkable comeback story in December when he stopped Simpson in the 10th round of their clash at Leeds’ First Direct Arena to claim the British, Commonwealth and European super-middleweight titles.

Not only had Williamson been trailing on all three cards at the time of the stoppage but the fight itself came only a few months after the Darlington man considered retirement following four defeats in five outings between December 2022 and April last year.

On Saturday night, Williamson will return as champion after Simpson decided to activate his contracted rematch clause and the pair will meet in the main event of a Boxxer show, live on DAZN.

Now Williamson has questioned his opponent’s decision to head straight back into the fire instead of attempting to rebuild elsewhere first.

“You’ve got to respect his decision to jump straight back in with me considering how it ended,” Williamson told The Ring.

“It was a dream come true but it wasn't a shock, I knew I was going to do it, I knew I would get to him and stop him. I said I was going to do it and I did it.

“But really, I think he’s been badly managed this time. To go straight back in for an immediate rematch, I think it’s backwards.”

Simpson, the 6-foot-3 Yorkshireman, enjoyed significant height and reach advantages over Williamson but the new champion believes his opponent has simply pushed himself as far as he can as a 168-pound fighter.

Simpson, 29, weighed 181 pounds when he made his professional debut in 2019 and constantly battles the scales to make championship weight. Williamson, meanwhile, is a former British champion at 154 pounds and feels reinvigorated by his move up in weight.

“There's no secret to him struggling to make weight,” Williamson (22-4-1, 16 KOs) adds. “He's massive.

“He's absolutely huge for 168lbs, so he obviously struggles to make the weight. And that fight was back eight months ago in December, so he's only going to struggle even more now we’re in August.

“And all this time between the two fights has allowed me to fully mould into a super middleweight. I'm a lot stronger, I'm punching a lot harder.

“So if I hit him in December, obviously this time, the way I'm feeling now, I think if I hit him now, I’m going to knock him out cold. I genuinely believe that. I'm super, super strong and fit. I believe I'm a real force in the super middleweight division."

Simpson (18-1, 13 KOs) responded to his first career defeat with a complete overhaul of his training team, electing to split from Mark Hurley, with whom he had spent all 19 professional fights, and join Rob McCracken in Sheffield.

But Williamson, who spent time training under McCracken during his amateur days, says not even a trainer change will help Simpson reclaim his titles.

He said: “Simpson basically came out and said that he’s going to try and box me this time, that he's going to try and keep it long.

“So him and his team are obviously going to try and win this on points and try and jab and move. But Callum isn’t a natural boxer and you can't teach somebody how to box in the few short months he’s been with Rob McCracken.

“Rob McCracken and Richie Woodall are great trainers — I know them from Team GB — but I can't see them making massive changes to Callum. I think when that weight cut kicks in, like I've said previously, he'll revert back to type and he'll hold his feet.

“It’s game over for him then.”