Naoya Inoue became a four-division world titleholder on Tuesday in Tokyo with an eighth-round knockout of previously unbeaten WBC/WBO beltholder Stephen Fulton, who was tough and game but completely outclassed by the Japanese superstar.

In his junior featherweight debut, Inoue (25-0, 22 KOs), a former undisputed bantamweight champ, took on the No. 1-rated 122-pound fighter in Fulton and dominated the 29-year-old Philadelphian. Inoue consistently beat Fulton to the jab throughout the one-sided fight and appeared just as comfortable walking down Fulton as he was waiting on the battle-tested technician.

Fulton (21-1, 8 KOs) wasn’t able to get off with any sort of effective offense until the middle rounds. Inoue’s speed, timing, quick feet and counter punching ability kept Fulton holstered and on the move, but The Monster continued to be the faster and busier boxer. Blood flowed from Fulton’s nose as early as Round 3.

Fulton, who had defeated four consecutive unbeaten contenders (including beltholder Brandon Figueroa) on his way to the top of the 122-pound division, was able to land some right hands in Round 5. The defending beltholder dug deep and tried to take the fight to Inoue in spots in Rounds 6 and 7, periodically catching Inoue with head-snapping right hands, but he continued to be out-jabbed and outworked by the odds/media favorite, who got off with three-punch combinations to the body and head whenever Fulton’s back touched the ropes.

If Fulton won a single round, it was Round 7. But his moral victory would be short lived.

A jab to the body-right to the head combination that landed just before the one-minute mark in Round 8 shook Fulton hard enough to make him lurch forward and touch the canvas with both gloves, but before referee Hector Afu could step between them to count it as a technical knockdown Inoue jumped in with a short hook that dropped the American.

THE SLOW-MO SHOT 🥶@NaoyaInoue_410 | #FultonInoue pic.twitter.com/X605OPAbuq

— Top Rank Boxing (@trboxing) July 25, 2023

Fulton beat the count and tried to tie up Inoue, but the former boxing wunderkind smelled blood and quickly cornered him, teeing off with body-head combinations until the fight was halted. Fulton was sagging to the canvas as the referee stepped in.

That’s a WRAP.@NaoyaInoue_410 x #FultonInoue pic.twitter.com/cnxig626LU

— Top Rank Boxing (@trboxing) July 25, 2023

Although Inoue was the odds favorite, most fans and boxing pundits viewed the Inoue-Fulton matchup as an even fight. Several respected members of the media picked Fulton to pull the upset via decision. But Inoue didn’t struggle at all. He made it look easy.

After the fight, Inoue said he had studied Fulton for a long time and had wanted this fight even before he unified all of the major world titles at bantamweight. He apologized to the fans inside the Ariake Arena for delaying the fight, which was originally scheduled for May, due to a knuckle injury, and then thanked Fulton for giving him the opportunity to win two 122-pound titles.

Marlon Tapales, who holds the IBF and WBA 122-pound titles, was in attendance and entered the ring after Inoue’s post-fight interview. Tapales said he wants to fight Inoue to prove he’s the real junior featherweight champion, to which Inoue replied:

“Let’s do this, this year!”

Undisputed next? 🏆🏆🏆🏆 pic.twitter.com/aIvVkfeoM0

— Top Rank Boxing (@trboxing) July 25, 2023

If you were one of those weirdos who refused to recognize or downplayed Inoue’s accomplishments and curiously left him out of pound-for-pound rankings, you’ve either got to admit that you were wrong about The Monster or quit watching boxing.

If you’re even thinking about disparaging Fulton for his performance against Inoue, please don’t go there. He dared to be great by traveling to Japan to face a fighter The Ring rates No. 2 in the pound-for-pound rankings and he should be commended. There’s no shame in losing to the greatest boxer in Japanese history.

More coverage of this fight will come later today from RingTV contributors Joe Santoliquito and Anson Wainwright.