Rookie professional Riki Kawamoto birdied the final hole to capture his breakthrough victory at the Sansan KBC Augusta on Sunday.
The 22-year-old, who earned a start at the Keya Golf Club through a sponsor's invite, closed with two-under-par 70 to finish the week at 17-under 272.
It was good enough for Kawamoto to edge penultimate stage leader Sang Hee Lee of South Korea by one stroke after the latter battled to a 72.
The feat made Kawamoto the youngest winner since the tournament's inception in 1973, bettering the record set by Yuta Ikeda when he won the 2009 edition at 23.
A delighted Kawamoto has dedicated his win to his sister Yui, a one-time JLPGA Tour winner, who turns 24 tomorrow.
“It was my first time playing in the last group on the final day since I became a professional, and I didn't know it would be such a tough battle,” said Kawamoto, who had previously impressed with a tied-fifth finish at the Japan Open in 2020.
“I’m so happy. Tomorrow is my sister’s birthday, so I think this is a good present for her!” my
Starting the day one shot adrift Lee, Kawamoto dropped two early bogeys on holes four and five but responded strongly with birdies on six, nine, 10 and 12 to open a four-shot advantage at one point.
Like his playing partner, Lee too bogeyed the same two holes before conceding another stroke on 11.
Lee attempted a comeback by birdieing three times on the four-hole stretch starting from 13 to draw level with Kawamoto, who bogeyed the 16, but he failed to make further ground in the last two holes.
Lee's hopes of forcing a playoff with Kawamoto went up in smoke when the latter buried the birdie putt to seal a sensational win on his only 15th JGTO start.
Lee lamented that nerves got the better of him.
"My driver was bad today and I couldn't keep the ball on the fairway," said Lee, a four-time Korean Tour winner.
“I was really nervous and couldn't concentrate. But it was really a joy to be surrounded by huge galleries. It feels good to have a lot of support.
"I will try my best in the next tournament and keep knocking on the door for a win. It's a big goal of mine to win in Japan and I want to realise it."
Apart from a well-deserved ¥20,000,000 windfall, Kawamoto's biggest reward is none other than a two-year full exemption through 2024.
This will surely put a smile on his face after failing to win his Tour card through the Qualifying Tournament.
Hyun Woo Ryu emerged as the second-best international finisher after shooting a 69 for a 12-under total to tie for fourth.
Four shots given away in the opening seven holes put paid to Scott Vincent's hopes to defend his title.
The Zimbabwean ended his campaign with a disappointing 76 to be tied for 12th on nine-over overall.