The Japanese pound-for-pound king took victory via a unanimous points decision in Saitama, unifying the bantamweight division in the process.
The scorecards read 116-111, 117-109 and 114-113 to Inoue, who now owns the IBF, WBA (Super) and Ring Magazine belts.
The unanimous points victory fails to tell the entire story however, with seasoned veteran Donaire proving to be by far the toughest challenge of the Japanese superstar’s career so far.
Inoue started the fight well, taking centre ring and using his superior footwork to get in and out of situations, dipping low to land straight jabs before following up with body shots. Donaire, the 36-year-old, is 10 years senior to his opponent but as the fight wore on looked more and more impressive somehow.
The second round is where things really changed. Inoue appeared to lose concentration and was caught by a right uppercut followed in with a left hook wish crashed into the right eye of the hometown fighter, who was immediately cut and in truth, hurt for the first time of his relatively short career.
“I had double vision from the second round,” Inoue admitted after victory.
“I was victorious and I am very proud of myself. I believe that I have a very bright future... Nonito Donaire was very, very strong. I think Donaire is a true champion.”
And perhaps it was that which was Inoue’s undoing through the fight, did he simply have too much respect for the four-weight world champion?
When you have punch power and a shot selection at the level Inoue does, it’s easy to rely on that and not be too concerned about what is coming back at you.
The punishment from Inoue really started to tell from the fifth round, unloading a barrage of body shots combined with a big left hook and an overhand right which Donaire somehow hung on to, backing away and holding his opponent to keep in it.
With Donaire hurt and tired, you would have been right in expecting him to crumble and succumb to the power of Inoue the same way so many of his opponents previously had done – he does boast an 89% knockout ratio, or he did before this fight. Donaire becomes only the third opponent to see the final bell against the now unified bantamweight champion.
It was the ninth that brought a big shock, Inoue’s blurred vision saw him caught by a huge right hand, forcing him to hold as the war of the battle was evident to see.
With two of the telling scorecards already so wide, Inoue had things in the bag but it was reaffirmed as he put down Donaire in the 11th, winding his opponent who somehow managed to beat the count and see himself through to the end of the 12th round.
Inoue goes on to become just the fourth man to win the World Boxing Super Series, sitting alongside Callum Smith, Oleksandr Usyk and Josh Taylor. He remains one of the world’s great fighters and at such a tender age will continue to rise up the ranks.
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