As if Naoya Inoue wasn’t already in rarefied circles, promoter Bob Arum suspects the Japanese dynamo may be even better than one of his former distinguished clients.

The 91-year-old founder of Top Rank Inc. was effusive in his praise for Inoue, in the wake of Inoue’s startlingly dominant eighth-round knockout of Stephen Fulton last month in Tokyo to win the WBO and WBC 122-pound titles. The win was particularly impressive because it was Inoue’s first fight in the junior featherweight division.

Now his American promoter, Arum, is inclined to believe that Inoue could be better than one Manny Pacquiao, the eight-division champion from the Philippines whose ascent captured the boxing imagination through the 2000s and early 2010s. Arum promoted Pacquiao for the majority of his career.

“Inoue is a tremendous, tremendous fighter, like we’ve never seen before, maybe since Manny Pacquiao—probably better than Pacquiao was,” Arum told Little Giant Boxing.

Although Inoue started his career at 108 pounds, Arum believes the phenom has the ability to go all the way up to the lightweight limit of 135 pounds.

“I think he has a chance to go all the way up, maybe even to junior lightweight or lightweight,” Arum said.

Arum, however, noted that 140 would be a bridge too far.

“Well, not 140—he’s not a big guy,” Arum said. “Look how Fulton—I was there, he’s so much bigger than he was, at 122. Inoue is something special.”

Inoue could be on track to unifying the 122-pound division later this year, if he takes on unified WBA and IBF junior featherweight champion Marlon Tapales of the Philippines.

Recently, Pacquiao informed the same outlet that he would be interested in helping Inoue move up in weight.

Arum, however, finds that assistance somewhat redundant.

“I love Manny, Manny knows boxing, but what’s he gonna add to Inoue?” Arum said. “Where is Inoue falling short where Pacquiao could help him?”

Sean Nam is the author of Murder on Federal Street: Tyrone Everett, the Black Mafia, and the Last Golden Age of Philadelphia Boxing