South Korea's Ko Jin-young led all the way to win the Australian Women's Open by three shots at Adelaide's Kooyonga golf course on Sunday.
Ko, 22, rolled in a short par putt at the last hole to clinch a wire-to-wire victory at 14-under to beat compatriot Choi Hye-jin on 11-under with Australia's Hannah Green on 10-under in third place.
Ko's victory allows her to take up full LPGA Tour membership for 2018.
The Korean was ranked 20th in the world before the tournament and will likely be close to the top 10 in this week's new rankings.
"My goal is to be rookie of the year," Ko said.
Ko began the tournament with a blistering seven-under 65 and was never headed nor seriously threatened.
Choi was the closest, jumping out of the pack to move within two shots at the turn in the final round, and still two shots back when they came down the stretch.
Ko hit a beautiful seven-iron shot to the 17th green, where the pond on the right represented potentially her only way of losing the Open.
Then she rolled the putt down the hill and into the cup from five metres.
She fired a closing three-under par 69, starting out with two birdies that stretched her initial lead of four shots to six.
She made some mistakes along the way, but none too serious, and hit 15 of the 18 greens in regulation.
In four rounds Ko only missed 11 greens, the best result in the field.
New Zealand's former world No.1 Lydia Ko struggled home to finish joint 19th at three-under after a closing par round of 72 after a second-round two-over 74 put her out of contention on Friday.
Her opening day effort had raised hopes she could contend after making major off-season changes to her support staff.
Ko replaced coach Gary Gilchrist with former PGA Tour professional Ted Oh, while Johnny Scott replaced Peter Godfrey as her caddie.