Hiroto Kyoguchi and Kenshiro Teraji both weighed comfortably within the junior flyweight limit in their battle for divisional supremacy.

Whatever issues arise during training camp, neither boxer has a history of struggling at the scales. That tradition carried over Monday afternoon (local time), with Kyoguchi registering at 107 ¾ pounds and Teraji at a trim-and-ready 107 ¼ for their highly anticipated WBA/WBC junior flyweight unification bout Tuesday evening at Saitama Super Arena in Saitama, Japan.

The bout marks just the second time ever that two reigning titlists from Japan meet in a unification fight. The lone other occasion came more than ten years ago, when then-unbeaten WBC strawweight champ Kazuto Ioka edged WBA titlist Akira Yaegashi in their terrific June 2012 slugfest.

Tokyo’s Kyoguchi (16-0, 11KOs) attempts the fifth defense of the WBA title he has held since New Year’s Eve 2018. The two-division titlist is 8-0 (4KOS) in major title fights, most recently stopping Esteban Bermudez in the eighth round of their June 10 title consolidation clash in Guadalajara, Mexico.

Tuesday’s fight marks the first in Japan in more than three years for Kyoguchi, while Kyoto’s Teraji (19-1, 11KOs) has spent his entire career in-country. The 30-year-old had work to do for this fight to move forward, however.

Teraji suffered a stunning, tenth-round knockout defeat to Masamichi Yabuki last September, losing his WBC title in the process. The title fight was postponed by nearly two weeks due to his previously testing positive for—and perhaps never fully recovering from—Covid. He was at full strength for the rematch, stopping Yabuki in the third round to regain his title on March 19, with both bouts taking place in his Kyoto hometown.

The winner will gain recognition as the division’s true lineal champion, though another title opportunity awaits in the form of whoever prevails in the evening’s co-feature.

Puerto Rico’s Jonathan ‘Bomba’ Gonzalez (26-3-1, 14KOs) came in right at the 108-pound divisional limit in defense of his WBO junior flyweight title. His challenger, Tokyo’s Shokichi Iwata (9-0, 6KOs) weighed 107 ¾ pounds for his first major title fight.

The event was put together with the intention of pairing the winner of the two title fights in a three-belt showdown in the first quarter of 2023. However, the Gonzalez-Iwata could be forced to next make a mandatory title defense, per a ruling during the annual WBO convention last week in San Juan, Puerto Rico.

Gonzalez won the WBO strap in a twelve-round decision victory over Elwin Soto last October 16 in Fresno, California. He has won four straight overall since returning to 108. Including a twelve-round points win over Mark Anthony Barriga in his first title defense on June 24 in Kissimmee, Florida.

Two more fights round out the televised quadrupleheader, which airs on ESPN+ in the U.S. (4:30 a.m. ET), Amazon Prime in Japan (5:30 p.m. JST), ESPN Knockout in Latin America and on DAZN in Europe.

Junto Nakatani (23-0, 18KOs)—a 24-year-old southpaw from Kanagawa—was 114 ½ pounds for his first fight back at junior bantamweight since vacating his WBO flyweight title less than one week ago. Mexico’s Francisco ‘Chihuas’ Rodriguez (36-5-1, 25KOs)—a former unified strawweight titlist who is now a top ten 115-pound contender—checked in at 115 pounds for their scheduled ten-round contest.

Masayoshi Nakatani (20-2, 14KOs)—no relation to Junto—was 134 ¼ pounds and Shuichiro Yoshino (15-0, 11KOs) was 135 pounds for their scheduled twelve-round regional title fight between Tokyo-based lightweights.

Jake Donovan is a senior writer for BoxingScene.com. Twitter: @JakeNDaBox