New Zealand teenager Lydia Ko seized a one-stroke lead in the Canadian Women's Open on Saturday, setting her sights on becoming the youngest winner in LPGA Tour history.
Ko, 15, fired an even-par 72 on the Vancouver Golf Club layout for an eight-under total of 208.
She was one stroke in front of a quartet of players: American Stacy Lewis and South Koreans Jiyai Shin, Inbee Park and Chella Choi.
"It's good to stay at the top of the leaderboard, but my first goal was to make the cut and hopefully top 15 or something," Ko said. "But to be up there is just an honor, especially playing against the world's best.
"Fifteen year olds don't lead at an LPGA event all the time. Like I said, I'm very surprised. But I've been playing really good golf and I've been really confident with my game."
Choi, who shared the overnight lead with Ko, carded a 73. Lewis climbed up the leaderboard with a 66, Shin posted a 69 and Park carded a 70.
It was two further strokes back to Sydnee Michaels (69) and Moira Dunn (72) on 211.
Park said she wasn't surprised to see Ko atop the leaderboard, but noted it might be hard for the less experienced youngster to close the deal on Sunday.
"I heard she was a really good player and some of these young amateurs can play golf," Park said. "It's not a big surprise, but I would be nervous if I was her -- so we'll see tomorrow."
The South Korean-born Ko could also become the fifth amateur to win an LPGA title and the first since JoAnne Carner in the 1969 Burdine's Invitational.
Ko won the US Women's Amateur championship a fortnight ago and in January whe won the New South Wales Open in Australia at 14 to become the youngest player to win an event on a professional tour.
Lexi Thompson is the youngest LPGA Tour winner, taking the Navistar LPGA Classic in September at 16.
Ko's round included three birdies and three bogeys. Her lead could have been a bit bigger but for a bogey at the par-four 18th, where she missed a four-foot putt for par.
"Today I tried to have more fun, but my score wasn't as good," Ko said. "I mean, 72 is better than 73 or any other score, so I'm pretty happy.
"Tomorrow, I'm just going to try my best. I've got to play my own game. I can't concentrate on what the other players are doing.
"If they shoot 66 and I shoot 68 and I lose, I can't control what they do."
World number one Yani Tseng, who led after the first round, struggled to a two-over 74 on Saturday. The Taiwan star is tied for 21st at one-under 215.