American Lexi Thompson made a 15-foot eagle putt on the par-5 18th hole to take a one-stroke lead into the final round of first women's major of 2016, the ANA Inspiration.
Trying to win the tournament for the second time in three years, 21-year-old Thompson shot a three-under 69 to reach 10-under 206 at Mission Hills in California.
New Zealand's world No.1 Lydia Ko (69) was one shot behind and tied second with South Korea's In Gee Chun (69) and Thailand's Ariya Jutanugarn (67).
Fifteen players were within four strokes of the lead.
Australia's Minjee Lee fell back with a 74 and was tied 27th at three under while countrywoman Karrie Webb had a 73 to be tied 59th at two over.
News that makes sense
Your trusted source for staying up-to-date with the world around you. Get free daily news updates and analysis, straight to your inbox.
Thompson struggled with her putting for most of the day but still managed a big finish.
Shit hit her approach shots to within two feet on both the par-4 15th and 16th holes to set up birdies.
She missed a 6-foot birdie try on the par-3 17th, then hit a 207-yard, five-iron approach pin-high to the left on the 18th to set up the eagle putt and claim the lead.
"To knock it in on 18 is always the most amazing feeling here," Thompson said.
"To finish like that definitely turns around my confidence. I feel really good going into tomorrow. ... I do know what it takes to win on this golf course. I mean, I absolutely love this golf course."
The 18-year-old Ko won the final major last season, the Evian Championship in September in France, and is coming off her 11th LPGA Tour title last week in Carlsbad.
"I felt like I struck the ball much better today and I hit a few more fairways, so the less time you're spending in the rough, the better," Ko said. "I feel like today I was able to control my shots and kind of have an idea where the ball was going to go."
Chun, 21, is returning from a back injury that sidelined her for a month. She was hurt when she was struck by a hard-case suitcase that rival player Ha Na Jang's father dropped down an escalator at the Singapore airport.
The 20-year-old Jutanugarn is winless on the LPGA Tour. At age 17 in the 2013 LPGA Thailand, she closed with a triple bogey to blow a two-stroke lead.
