Junto Nakatani has revealed his struggles to make the super flyweight limit contributed to him moving up to bantamweight to challenge the WBC champion Alexandro Santiago. 

On Saturday, at the Ryogoku Kokugikan in Tokyo, he fights at 118lbs for the first time, having made one defence of the WBO 115lbs title he so impressively won when stopping Andrew Moloney at Las Vegas’ MGM Grand.

Having previously also won the WBO flyweight title, at the age of 26 he is on course to become a three-weight world champion, and he told The Ring: “I would have to admit that my weight issue was the decisive factor in moving up a weight class. I knew I could have stayed at junior bantamweight a bit longer, but when I actually moved up a weight class, I felt my body getting bigger and bigger.

“I don’t feel any change myself, but some of those who come around to the gym eagerly commented that I box faster and sharper. I see these objective observations in a positive light and will try to showcase more of my ability in the fight. To be a bit more precise, I do care about ‘instantaneous’ speed, which I have trained with a particular emphasis on, and I think it is easier to demonstrate this in my new division. With these in mind, I am more determined to build a solid bantamweight body, always with higher expectations of myself.

“I knew I could adapt to bantamweight whenever I moved up and I knew I definitely had that potential. I’m not worried about going straight to fighting [for] a championship without any tune-up bouts. I am instead focused on getting in shape for this weight class. Since I have never had the experience of challenging a champion in my career, it is easy to get pumped up for the fight to accomplish something completely new.”

Mexico’s Santiago, 28, won the vacant title in July 2023 when he outpointed the once-great Nonito Donaire.

“By no means do we feel this is an easy fight,” said Rudy Hernandez, Nakatani’s trainer, who incidentally is based in Los Angeles. “I think it’s complicated but we’re training to bring the best Junto to this fight. 

“He’s sharp and stronger because weight loss won’t be as significant. Sparring is key for fighting day. I use old ways better than new boxing. I train fighters, not human beings.”