Having started slowly in Haikou, he fired a three-under 69 – the lowest round of the tournament – on the final day to earn a play-off against Thailand’s Supawitch Songklod.

He rolled in a 15-foot putt on the second sudden-death hole for eagle and the win.

And Schadewitz says that uncoachable competitive hunger means Kho has all the potential for a successful pro career.

“He’s quite tall and thin at the moment and needs to put on some muscle, but he’s got everything else except strength,” said Schadewitz, who often worked with Kho in association with his regular coach, Discovery Bay Golf Club’s Mark Mossip.

“His first step will be the college route, I know he wants to go to uni in US which is great – when I look at him I think the sky’s the limit.

“What I find really stands out is he’s a competitor, he really enjoys the moment, loves the challenge and that’s what impresses me most.

“You can’t coach that, he can add the strength in the gym, he’ll fill out over time going through college and working out regularly and who knows how good he can get.”

Kho, back in school after a late-night return from Hainan, said modestly: “It’s nice to hear that from Brad, I’ve always looked up to him and he’s helped me a lot over the past few years.

“It’s nice to get some compliments but we both know what we need to work on.”

DB Golf Club’s Mossip has been coaching in Hong Kong for 18 years but gave the impression Kho was one of the charges he’s been most impressed with.

“I have to give the parents credit, he’s one of the most polite kids you’ll ever meet, academically he’s excellent, in the top three of his class and he’s just been named athlete of the year at Discovery College.

“The last few years he’s really started to shine, he’s grown about eight inches in two years so he’s got some more length ... just his record in the last six month he will have impressed US colleges. The target and his ambition is to play pro golf.”

Kho, whose father is Chinese and mother Japanese, said he didn’t expect much in Hainan, but once he got into the groove on the final day had no doubt he’d win.

“I just finished my mock exams for IB and haven’t practised in a solid month,” he said. “But on the last day I knew I still had my game, got off to quick start and never looked back.

“The eagle putt on the last hole, I was so confident, I just knew it was going to go in.”

The year 12 student has reached out to “about 40” colleges in the US as he tries to win a scholarship, and will head to California and the eastern US this summer to play in tournaments and let coaches take a look at him.

“It’s just something I’ve just got to do if I want a chance of playing golf as a career,” he added.

“There’s two aspects, I want a school with good academics first then look at golf rankings, what sort of players on certain teams, how much of a chance I’d have to play regularly etc.”

Another HK player, Iris Wang Xinyi, won the girls’ 11-14 division with a score of 241, with New Zealand’s Rose Zheng winning the overall title.

The event, in which more than 110 youngsters took part, is one of the most prestigious junior tournaments in the region.

Hong Kong youngsters won it in 2009 (Steven Lam) and ’10 (Terrence Ng), but Kho’s win is the first since then. He was runner-up in last year’s event.

Young female golfer Tiffany Chan Tsz-ching recently turned pro on the Symetra Tour after finishing her golf scholarship at the University of Southern California.