Lydia Ko admits she's surprised by the speed of her transition from being an amateur to becoming a professional golf champion.
The 16-year-old showed composure that belied her age in coming from three shots behind midway through the final round to claim a three-shot victory in the Swinging Skirts World Ladies Masters in Taiwan.
Ko's success, and a cheque for $US150,000 ($NZ181,000), came in just her second tournament as a professional.
It follows her 21st placing on debut in the LPGA's season-ending CME Group Titleholders Championship in Florida in November.
"I'm really surprised," she said after walking off the final green at the Miramar Golf and Country Club in Taipei.
"I didn't really have this coming. I think playing in the CME two weeks ago definitely helped me with all the nerves."
The Aucklander said she felt the butterflies before the final round, when she trailed overnight leader Ryu So-yeon of South Korea by a stroke, but she told herself just to concentrate on her game.
"I always say I can't control what the opposition does," she said.
"All I can do at the end of the day is control my game and that's even hard by itself."
Among those who sent their congratulations was All Blacks fullback Israel Dagg, who in October had helped Ko announce her decision to turn professional via a YouTube video.
"Well done lyds maybe I can caddie your next tournament yeah??? awesome stuff so proud," Dagg tweeted.
Ko's coach, Guy Wilson, who watched on television as she clinched the win, said she showed she was a player for the future.
"She is someone that everyone will talk about for a long, long time," he said.
"Watching her cruise through each round and not struggle when the foot was pushed down on her - she showed everyone needs to keep up otherwise she will cruise right on past."
For the final round, Ko was in the same group as the world's top-ranked golfer, South Korean Inbee Park, and world No.5 Ryu, a former US Women's Open champion.
But she was undaunted by the company around her, even as Ryu opened up a three-shot lead at the turn.
The momentum began to swing her way at the par-four 10th, when she converted a 2m birdie putt while Ryu dropped a shot after finding a green-side bunker.
Ryu then conceded the lead on the par-three 14th, when she four-putted for a double-bogey.
Ko went on to finish with a three-under 69 to be 11-under for the 54-hole tournament, while Ryu carded a 73.
Park was third, one stroke further back, after a 70.
As an amateur, Ko entered 25 professional tournaments, winning four of them, including the Canadian Open, an LPGA Tour event, twice.
She didn't once miss a cut and had to forgo more than $1 million in prize-money.