The unbeaten Inoue was declared the winner when Doheny was left hobbling and unable to proceed following a barrage to the physique from the person nicknamed “Monster.”
The 31-year-old Inoue took his document to 28-0 with 25 wins by knockout.
He was making his second protection since turning into the undisputed super-bantamweight world champion final December.
He is simply the second man to turn into undisputed world champion at two completely different weights because the four-belt period started in 2004. American Terence Crawford was the primary.
Inoue was preventing for the primary time since he beat Mexico’s Luis Nery in entrance of 55,000 followers on the Tokyo Dome in May.
That combat noticed Inoue knocked down for the primary time in his profession however he by no means appeared in severe hazard in opposition to the 37-year-old Doheny.
Inoue needed to be affected person in opposition to his cautious opponent however he started to land some large physique blows because the combat progressed.
The bout got here to an abrupt halt when Doheny instantly started limping about 20 seconds into the seventh spherical, having appeared to injure his hip.
He was unable to stroll and needed to be helped from the ring by his workforce.
Doheny, who held the IBF super-bantamweight world title from 2018 to 2019, noticed his document drop to 26-5, with 20 KOs.
On the undercard, Japan’s Yoshiki Takei retained his WBO world bantamweight title with a unanimous resolution win over countryman Daigo Higa.
Takei was making his first protection after taking the title from Australia’s Jason Moloney in May.