A win on Saturday for Kazuto Ioka will once again see his name etched in the record books.

It’s far from his end game, however.

Japan’s lone-ever male four-division titlist is set for his WBO/WBA junior bantamweight unification bout versus visiting Joshua Franco. The two-belt takes place this Saturday on TBS-Japan (5:00 p.m. local time/3:00 a.m. ET). With a victory, the 33-year-old Ioka would become the only Japanese fighter to unify at least two belts in two separate weight divisions, having previously done so at strawweight.

The goal from there would be to add the remaining two junior bantamweight straps to his collection.

“I want unify the four titles [at 115 pounds] to prove that I am the best in this weight class,” Ioka told BoxingScene.com through translator and promoter Yusuke Ninomiya. “I want to have a showdown versus [lineal/WBC champion Juan Francisco] Estrada next.”

Ironically, Ioka’s unification bout comes as a direct result of Estrada (44-3, 28KOs) opting against a WBA title consolidation bout with San Antonio’s Franco (18-1-2, 8KOs). The two were due to meet earlier this summer, but Estrada elected to relinquish his WBA ‘Super’ title, allowing Franco to receive an upgrade to full WBA 115-pound champ after previously holding a secondary version of the belt.

Estrada instead proceeded with a rubber match versus former four-division champion Roman ‘Chocolatito’ Gonzalez (51-4, 41KOs), whom he outpointed over twelve rounds on December 3 in Glendale, Arizona. Franco was ringside for the occasion, while Ioka watched—unimpressed—from his training camp.

“I thought it was a boring match, to be honest,” claimed Ioka.

Estrada walked away as a two-time WBC junior bantamweight champion while also lodging the fifth defense of his lineal championship. Afterward, the two-division champ from Hermosillo, Mexico told BoxingScene.com of his desire to next face the Ioka-Franco winner as he is permitted a voluntary title defense while the WBC sorts out his next mandatory title challenger.

Franco has already expressed his interest in such a fight. Ioka is just as keen, which would only leave IBF champ Fernando Martinez—who is in talks for a mandatory title defense versus Jade Bornea—as the last piece of the puzzle to crown an undisputed junior bantamweight champion.

For now, another piece of history is well in reach for Ioka. He already prevailed in the first-ever unification bout between two reigning Japanese titleholders when he outlasted Akira Yaegashi in their fiercely contested June 2012 WBC/WBA strawweight title clash.

A win on Saturday gives him an unprecedented (in Japanese boxing) second unified title reign. It would come less than three weeks after countryman Naoya Inoue became Japan’s first undisputed champion in the multi-belt era following his Dec. 13 eleventh-round knockout of Paul Butler in their lineal/WBA/WBC/IBF/WBO bantamweight championship in Saitama, Japan.

Chasing that level of history is the true end game for Ioka, more so than the next benchmark within reach.

“It’s just a passing phase for me,” Ioka said of potentially becoming a two-division unified champ. “I want to prove that I am the best in this weight class and always aim for the next level.”

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