Naoya Inoue knocks out Jamie McDonnell in first round

Japanese star Naoya Inoue, already a two-division world titleholder and one of the pound-for-pound best in boxing, added to his growing reputation with a sensational performance on Friday.

Inoue more than lived up to his nickname of "Monster" as he destroyed secondary bantamweight titlist Jamie McDonnell in a first-round knockout victory, winning a belt in his third weight class. The bout was the main event of a world-title doubleheader that streamed live on ESPN+ from the Ota-City General Gymnasium in Tokyo.

Inoue (16-0, 14 KOs), 25, won a junior flyweight world title in his sixth fight in 2014 and then won a second world title at junior bantamweight in his eighth fight later that year. He defended it seven times before vacating it earlier this year to move up in weight again for a shot at McDonnell (29-3-1, 13 KOs), 32, of England, and Inoue made it look easy despite a 5-inch height deficit against his 5-foot-10 opponent.

McDonnell won his 118-pound belt in 2014, but he had never seen the combination of speed, power and skills that Inoue showed him in his seventh title defense. Inoue attacked him to the body immediately and backed him up. Then he wobbled McDonnell with an overhand right.

Inoue was relentless with his punches, and seconds after the right hand hurt McDonnell, he landed a left hand to the body that sent him sprawling to the canvas.

Although McDonnell was up at the count of five, he was in big trouble. Inoue backed him into the ropes and unleashed a furious nine-punch flurry, rocking him badly with a left hook to the head and with a right hand that dropped him again as referee Luis Pabon was intervening to wave off the fight at 1 minute, 52 seconds.

McDonnell had spoken ahead of the fight about an intense 12-week training camp to prepare for Inoue, but it served little good.

With the victory secured, Inoue made official what was already an open secret in boxing -- that he will compete in the eight-man, single-elimination World Boxing Super Series bantamweight tournament that was recently announced and will begin in September.

"I'll participate in the World Boxing Super Series to face other world champions with pleasure," Inoue said.

World Boxing Super Series officials recently announced they would stage tournaments in three divisions in their second season and began by unveiling the partial field at bantamweight at a news conference in London. With five slots remaining, organizers introduced world titleholders Ryan Burnett (19-0, 9 KOs), 26, of Northern Ireland; Zolani Tete (27-3, 21 KOs), a 30-year-old southpaw from South Africa; and Emmanuel Rodriguez (18-0, 12 KOs), 25, of Puerto Rico. One of them will go to Inoue, who as secondary titlist is the mandatory challenger for Burnett.

In the co-feature, junior flyweight world titleholder Ken Shiro (13-0, 7 KOs) retained his 108-pound belt in a rematch with former titlist Ganigan Lopez (29-8, 18 KOs) by knocking him out with a brutal right hand to the body at 1 minute, 58 seconds of the second round.

Last May, in their first meeting, also in Tokyo, Shiro, 26, won a majority decision -- 115-113, 115-113 and 114-114 -- against Lopez, 36, a southpaw from Mexico, to claim a 108-pound world title. The rematch, Shiro's third title defense, was nowhere near as competitive. After a first round in which little happened as Shiro and Lopez sized each other up, Shiro took out his opponent with the body shot in the second round. Lopez went down to all fours, and referee Vic Drakulich counted him out.

"Last night, my father advised me to attack with a right shot to the midsection," Shiro said. "That paid off. I thank him for his suggestion, as I didn't expect such a quick finish."