By Jake Donovan

All four title participants made weight for a loaded doubleheader Friday evening in Kyoto, Japan.

Headlining the bill - which airs live on Nippon TV (NTV) in Japan - unbeaten Shinsuke Yamanaka attempts the 10th defense of his bantamweight title as he faces former super flyweight titlist Liborio Solis. Both fighters came in under the 118 lb. limit - Yamanaka tipped the scales at a fighting-ready 117.75 lbs., while Venezuela's Solis weighed in at 117.5 for his first eligible title fight in more than three years.

The bantamweight division has been without a lineal champion in nearly 30 years, but Yamanaka (24-0-2, 17KOs) has emerged as the de facto leader over the course of his title reign of more than four years. 

Some of the shine was finally knocked off in his most recent title defense, struggling to a 12-round points win over former bantamweight titlist Anselmo Moreno last September. The night marked the second time in three bouts that the unbeaten 33-year old was extended the distance, after having registered six knockouts among his first seven title fights.

The outcome of the win over Moreno was hotly disputed, but nevertheless extending Yamanaka's reign, having celebrated his four-year anniversary as champ last November. 

Solis (23-3-1, 10KOs) fights outside of The Americas for just the third time in his pro career, with all such road trips taking place in Japan. He enjoyed the best and worst of times in his two previous visits to the Far East, both of which came in 2013. Solis snatched a super flyweight title in his May '13 victory over Kohei Kono, trading knockdowns with the local favorite before shading it on two of the three scorecards.

His return visit, however, left a stain on his career. Solis showed up more than two pounds over the super flyweight limit for a planned title unification clash with Daiki Kameda. The title was vacated at the scales, with Solis going on to win a split decision but leaving beltless as a result of his lack of discipline during training camp.

Solis has since added seven more victories to a current 14-fight win streak. The most recent occasion came last December, scoring a nine-round decision over Jonathan Baat in Panama City, Panama. The show also included Shane Mosley in his continued comeback tour as well as Luis Concepcion gaining long-awaited revenge on his two-time conqueror Hernan 'Tyson' Marquez. 

In the evening's chief support, Yu Kimura meets Mexico's Ganigan Lopez in the first defense of his junior flyweight title. Kimura was well within the 108 lb. divisional limit, checking in at a light 106.9 lbs. Lopez weighed 107.25 lbs. in his second crack at a major title.

Kimura (18-2-1, 3KOs) pulled off one of the biggest upsets of 2015, albeit in a controversial 12-round decision nod over Pedro Guevara last November. The victory netted the 32-year old boxer the junior flyweight title, additionally extending his current win streak to nine straight.

Lopez (26-6, 17KOs) fights outside of Mexico for just the third time in his career. The other two occasions came back-to-back,  fighting in Nicaragua in July '06 and Japan in April '07.  

The showdown with Kimura marks his second crack at a major title,  both of which taking place in a span of eight months. Lopez came up short in a 12-round decision to then-champ Guevara last July in his opponent's hometown of Mazatlan, Mexico.

Jake Donovan is the managing editor of BoxingScene.com. Twitter: @JakeNDaBox