The Dragon breathes fire
Click on the photos above to see scenes from fight night.
"The Dragon" rarely looked in danger of relinquishing his eight-year grip on the World Boxing Association (WBA) crown, despite being briefly put on the back foot in the seventh round by Kimura.
John recovered well and dominated the remaining rounds to emerge with a unanimous 118-109, 118-109 and 117-110 victory, delighting a 4,000-strong partisan crowd at Singapore's Marina Bay Sands arena.
John, who has faced calls to fight more often outside of Asia, where he has a huge fan base, now moves to 47 wins, including 22 knockouts and two draws. Kimura falls to 24-5-2, with nine wins within the distance.
Hard-hitting Kimura had promised a tough fight but was little match for John's crisp boxing and effective punching. However, he earned warm praise from the Indonesian champion.
"I tried my best... Kimura is the toughest boxer from Japan I have ever fought," said the jubilant John, 32.
On the undercard, Indonesia's Daud Yordan stunned the Philippines' Lorenzo "Thunderbolt" Villaneuva with a second round technical knockout to take home the vacant International Boxing Organisation featherweight belt.
The fight referee was forced to award the fight to Yordan after Villanueva appeared visibly dazed 66 seconds into the second round, reeling from quickfire knockdowns by the Indonesian.