CANBERRA, Australia (AP) -- Teen star Lydia Ko shot a 10-under 63 on Thursday to take the first-round lead in the LPGA Tour's season-opening Women's Australian Open.
The 15-year-old amateur won the New Zealand Women's Open on Sunday for her third victory in a professional tournament. Last year, Ko won the New South Wales Open to become the youngest player to win a pro tour event and the Canadian Open to become the youngest LPGA Tour winner. She also won the U.S. Women's Amateur.
Ko opened with a bogey on the 10th hole, birdied the next four holes and eagled the par-5 15th. She bogeyed the 16th and birdied Nos. 17-18 to make the turn at 6-under 30 at Royal Canberra. The South Korean-born New Zealander added birdies on Nos. 2-4 and 6, dropped a stroke on No. 8 and closed with her 11th birdie.
"I was in a really good group to start off with," said Ko, grouped with top-ranked Yani Tseng and Michelle Wie the first two rounds. "I was pretty nervous when I saw the draw that I was playing with two of the big names, but I mean the weather was beautiful, I think we all enjoyed our time out there."
While still in high school, she hasn't had time to spend in class this year due to her golf commitments.
"I've got the Thailand Open next week and then the New Zealand LPGA Championship," Ko said. "After that, I will start opening books."
Colombia's Mariajo Uribe was a stroke back while South Korea's Jiyai Shin was two behind after a 65. Canada's Rebecca Lee-Bentham, playing in one of the final groups of the day, Ayako Uehara of Japan and South Korea's Lee Mi-hyang shot 66 to be tied for fourth.
Tseng, the Australian Open winner at Commonwealth in 2010 and 2011, opened with a 68 in her first tournament of the year. Wie, making her first appearance in Australia, shot a 74.
"I played very solid," Tseng said. "I didn't putt as good, but I'm pretty happy I shot 5 under for the first round of the year."
Tseng was impressed with Ko's maturity.
"Five under is still a good day ... but to Lydia 5 under is nothing," she said, laughing. "I mean it was very fun to watch her play golf today.
"She still looks 15. I don't know how she hit the ball that well. I think she pushed me up a little bit, too. ... She was on fire. She could've shot a 12 or 13 under today."
Stacy Lewis shot 69 and fellow American and defending champion Jessica Korda had a 70.