NATHAN Cleverly has admitted he's come out of the dark and into the light mentally in a year of change.

The 27-year old Cefn Fforest fighter has jumped up 25lbs, the biggest weight differential in professional boxing to resume his career as a cruiserweight.

The former WBO light heavyweight champion of the world returned to the ring for the first time in nine months on Saturday as he destroyed Shawn Corbin inside two rounds.

It finally eradicated the memory of Cleverly's brutal first career defeat against Sergey Kovalev as he moves onwards and upwards.

Cleverly hasn't just switched weight categories, having also changed promoters and switched trainers, now working with former cornerman Darren Wilson full time instead of his father Vince.

The short-term goal is a lucrative payday against domestic rival Tony Bellew, but Cleverly knows he's well down the pecking order at his new weight.

He's chasing the chance to become a two-weight world champion and despite that aim being a far way off, Cleverly insists he couldn't be happier in himself.

"I'm back with a bang and back with a smile, I feel strong again, I feel sharp, I feel fresher and more energized mentally and physically and it's great to be able to say that," he said.

"My training camp went really well and I feel physically and mentally spot-on once again.

"It's a big gamble moving up in weight and Saturday is an example of that, Shawn Corbin was a unit with muscles everywhere, but I feel stronger as well and crisp and sharp at the weight.

"There are plenty of big cruiserweight but what they don't have and will struggle to deal with is my speed.

"I'm going to grow into the weight even more and I feel really well. I've grown into the division over nine months and I needed the time to mentally refresh."

Cleverly is confident he can achieve all his dreams despite the setback of losing to Kovalev.

"It's my Rocky Balboa time now, I'm at the bottom and I'm going to punch my way back to the top," he explained.

"My first career defeat got me crashing down to reality after being on top of the world, but sometimes you need these setbacks to keep you grounded and hungry.

"That's what I am now, the hungry fighter, I'm going to climb my way back up and I intend to enjoy the journey.

"Chapter one was fantastic and now here I am six weights higher than where I debuted, as a welterweight."

Cleverly explained his satisfaction at teaming Wilson after previously spending a few weeks in London working with Adam Booth.

"I've made a lot of changes in the last nine months including my trainer, a lot has happened and so far it's gone great," he said.

"Darren is a friend as well as a trainer and we've worked hard, it's the two of us together and we've gone back to basics, travelling for sparring.

"We work well together and it's a good match-up.

"I'm more enthused about boxing in general now, I feel stronger an