The ambitious start to his career was a firm indication that Naoya Inoue was destined for greatness.

He now finally gets to chase history.

The unbeaten three-division and reigning lineal/WBA/WBC/IBF bantamweight champ has soared to near the top of any credible pound-for-pound list through more than eight years on the title stage. A shot at immortality is now within reach as Inoue is a heavy favorite to fully unify the division versus WBO titlist Paul Butler. With a win, Inoue realizes a longtime dream of becoming Japan’s first ever undisputed champion in the multi-belt era.

“I have always pictured myself becoming the first Japanese undisputed champion,” Inoue told BoxingScene.com. “I wanted a unification fight to become the undisputed champion when I was fighting at Super Flyweight (115 pounds).”

Their championship clash takes place on Tuesday at Ariake Arena in Tokyo (ESPN+, 2:30 a.m. ET).

Inoue (23-0, 20KOs) claimed his first major title in just his sixth pro fight, dethroning Adrian Hernandez via sixth round knockout to win the WBC junior flyweight title in April 2014, one week prior to his 21st birthday. The reign was short-lived, with the prodigious star from Yokohama, Japan moving up to the 115-pound division with a second-round knockout of long-reigning WBO champ Omar Narvaez in December 2014.

Six title defenses followed, though none in unification bouts. Inoue even took the step of making his U.S. debut, appearing on the September 2017 “Super Fly” card featuring the division’s top talent at StubHub Center (now Dignity Health Sports Park) in Carson, California. Unfortunately, he wouldn’t come any closer to getting any of them in the ring, eventually making his way to bantamweight where he has since established himself as the true champion.

Inoue ran through the bantamweight field in the World Boxing Super Series, bringing a secondary WBA title into the tournament and exiting with the IBF and WBA ‘Super’ belts in tow. The latter came in a thrilling twelve-round win over Nonito Donaire, overcoming a cut and a broken orbital bone to prevail in their Fight of the Year-level slugfest.

This past June saw Inoue add the WBC belt to his collection in a far easier time with Donaire, blasting out the Filipino legend in the second round of their lineal/WBA/WBC/IBF unification bout. By that point, Butler (34-2, 15KOs)—a 34-year-old from Ellesmere Port, Cheshire, UK—claimed the WBO belt and was more than willing to land a four-belt unification clash with one of the sport’s very best boxers in the world.

It helped delay Inoue’s decision to eventually move up in weight, already with aspirations of becoming a two-division champion as he plans to conquer the 122-pound junior featherweight division.

“I’m happy that I have this opportunity to become undisputed champion at bantamweight,” noted Inoue. “Once I am successful, I aim to do the same at (122).”

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