South Korean Lee Ji Hee shot a stunning 5-under-par 67 in the final round to seal only her second tournament victory in the 60 million yen Promise Ladies on Sunday.
Starting the day three shots off the lead, Lee reeled off six birdies against just one bogey to finish on a 8-under-par total of 208, two strokes clear of Masaki Maeda in second.
"It feels like I'm dreaming. I didn't really think I had a chance of winning today so I'm absolutely delighted," said Lee after winning her first title since the 2001 Daio Paper Elleair Ladies Open.
Teeing off the day in fifth, Lee slipped further back after three putting on the first for a bogey but began to find her form and picked up shots on the fifth and the eighth.
Lee ran in a 12-foot birdie putt on the 10th to pick up her third shot of the day and went top of the leaderboard for good with three consecutive birdies from the 14th.
"I got a bit of a shock when I looked up at the scoreboard on the 15th and saw myself in the lead. I got into a good rhythm and played real well, especially on the back nine," said Lee.