Naoki Fukuda

For as great as Naoya Inoue has been throughout his run as three-division champion, Tuesday morning's destruction of unified 122-pound champion Stephen Fulton Jr. just placed him into a whole different stratosphere. 

Inoue (25-0, 22 KOs), the reigning pound-for-pound king, scored the most emphatic victory of his increasingly legendary career by becoming a world champion in a fourth division following an eighth-round TKO of Fulton (21-1, 8 KOs) to commandeer the WBC and WBO super bantamweight titles. 

The 30-year-old Inoue dominated from start to finish in front of his adoring home crowd inside Tokyo's Ariake Arena. But it was the ease in which he systematically demolished Fulton, among the most well-rounded champions in the sport, that turned boxing's current P4P debate into anything but, even as the sport awaits Saturday's Errol Spence Jr.-Terence Crawford showdown for the undisputed welterweight title. 

"Last year, I became an undisputed champion. I returned all the belts and came up to super bantamweight," Inoue told the crowd after the fight. "Everything I was thinking about was to fight [Fulton] this year. Unfortunately, I got an injury and had to postpone this fight. I'm sorry to my team but thank you so much to Fulton for accepting this fight and I'm so happy right now."

Fulton was put on the defensive from the start and was never able to gain Inoue's respect with effective offense. Not only did Inoue bloody the nose of Fulton in Round 3, he simply beat up the unified champion at any distance, including chasing him down with four-punch combinations while on the move.  

Inoue outlanded Fulton, 114 to 47, according to CompuBox, and ravaged Fulton to the body throughout. But it was the fact that Inoue so easily carried his power up to a fourth weight division that continued to raise the ceiling of what might be possible for the rest of Inoue's career. 

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Although Fulton hung tough throughout, the pressure finally broke him in Round 8 as Inoue landed a vicious combination of a right hand and a winging left hook to drop him. After Fulton got back to his feet, Inoue swarmed on him in the corner to drop him once more as referee Hector Afu waived off the fight at 1:14 of the round. 

After the victory, Inoue welcomed fellow unified 122-pound champion Marlon Tapales into the ring to hype the potential of a November undisputed clash between the two-belt titleholders. Inoue, who knocked out Paul Butler in December to become the first undisputed champion in 118-pound history, could become boxing's first two-weight undisputed king with a win. 

"I want to fight Naoya Inoue because I want to prove to myself that I am a champion," Tapales said. "Let's do this, this year."