The defending champion (32-0, 27 KOs) set the wheels in motion for a future fight last year, calling out his fellow multi-weight star at the JBC awards ceremony. Both promised to remain undefeated and despite a scare along the way in the final days of 2025 abroad on Saudi shores, May 2 at Japan's Tokyo Dome now can't come soon enough.

Nakatani (32-0, 24 KOs) was given a rough welcome to the junior featherweight division, eeking past a spirited Sebastian Hernandez showing on the Ring V card topped by Inoue's one-sided title defense against Alan Picasso on December 27.

"I saw the fight in Saudi and against an opponent like that, can really rate it [Nakatani's performance] highly. It's made Junto a stronger boxer, so I'll be on my toes and ready to go on fight night," Inoue said when asked about the skilled southpaw.

Bullish as expected in response, Nakatani insisted he has more to show after some defensive vulnerabilities were laid bare during what many believed to be a showcase offering against the unheralded Hernandez.

"I've managed to get to this point undefeated so all that is left is to become world champion [in another division]. I want to make it the best match possible, will be happy if everyone can come and watch. I've learned a lot from the [Dec. 27] fight, been able to grow a lot by facing that and you'll see just how much I have on May 2."

Rudy Hernandez, Nakatani's LA-based coach, has been vocal about snaring this Inoue fight at the right time before 'The Monster' declines to diminish the sense of achievement.

Inoue enters this after consecutive decision victories for the first time in his 14-year pro career and suffered knockdowns en route to rallying stoppage victories against Luis Nery and Ramon Cardenas in successive years.

Nonetheless, Hernandez struck a more respectful tone in acknowledging the size of the task at hand for his charge, four years Inoue's junior and another tall foe.

"I really believe he [Nakatani] will have to come with his best abilities and needs everything to beat Naoya, who I consider the world's best fighter right now. The best fighting the best."

In the evening's chief support, Takuma Inoue (21-2, 5 KOs) will make the first defense of his WBC bantamweight world title against Kazuto Ioka, whose divisional debut was markedly different than Nakatani a week later to cap an eventful 2025.

"I'm really looking forward to competing against Kazuto on such a big stage, don't feel like I'm beating the enemy or anything like that, I want people to see how I can overcome and beat such a legend," the 30-year-old said when previewing their matchup.

Ioka, who stopped Maikel Ordosgoitti in four rounds on his bantamweight debut December 31, stressed his gratitude at being given a shot at making more history.

"I want to achieve my goal of becoming a five-weight world champion, beating Takuma will be a very high hurdle as he has a lot of overall skills."

Naoya Inoue (32-0, 27 KOs) vs. Junto Nakatani (32-0, 24 KOs) for Inoue's Ring, undisputed 126-pound world titles

Takuma Inoue (21-2, 5 KOs) vs. Kazuto Ioka (32-4-1, 17 KOs) for Inoue's WBC 118-pound world title

Featherweight: Toshiki Shimomachi (22-1-3, 12 KOs) vs. Reiya Abe (28-4-2, 10 KOs)

Welterweight: Sora Tanaka (5-0, 5 KOs) vs. Jin Sasaki (20-2-1, 18 KOs)

Flyweight: Kosuke Tomioka (11-4, 8 KOs) vs. Shogo Tanaka (5-0, 3 KOs)

Super middleweight: Deok No Yun (10-2-1, 8 KOs) vs. Yutio Moriwaki (1-0-1)

Bantamweight, 8 rounds: Yoshiki Takei (11-1, 9 KOs) vs. Dekang Wang (9-1, 3 KOs)