Brooke Henderson birdied the final three holes for a second successive 64 at the Evian Championship on Friday.
Chasing a second Major to sit alongside the 2016 Women’s PGA Championship, the 24-year-old Canadian finished on 14 under par and three ahead of Nelly Korda.
Korda, the former world No 1 on the road back from a blood clot in her arm, also had a sparkling finish to a 67.
She birdied the 17th from six feet and then eagled the last, hitting her hybrid second to inside three feet.
Korea’s Ryu So-yeon was tied for third on eight under par after a 66.
South Africa’s Ashleigh Buhai sits on four under after shooting a second-round 70, while Paula Reto and Lee-Ann Pace missed the cut.
Henderson recently switched to putting left hand low and it has transformed her results.
She won her 11th LPGA Tour title at the Shoprite Classic last month and she is keen to add to her Major success this weekend.
“It feels really great to get such a fast start in a Major. It’s been a while,” reflected the player whose older sister, Brittany, is her regular caddy.
“I’m hitting the ball really well and been holing a lot of putts the last couple of months. That’s been the difference.
“This is the start of a fun run in Europe. We have the Scottish and British Opens over the next two weeks. Now I just want to keep it going over the weekend.”
Korda, after an opening 64, had a fairly routine round, but the finish catapulted her back up the leaderboard.
“My ball-striking wasn’t as good today and I’ve been struggling with jet lag,” said the 23-year-old. “But it’s been a pretty good, in fact super good, first two days. I can give myself a little pat on the back.”
World No 1 Ko Jin-young has still not captured the form of last year but a 69 for seven under kept her in contention.
She was on the same mark as 2015 Champion, Lydia Ko, and overnight leader Ayaka Furue, who added a 72 to her 63.
Ko had an adventurous finish. Ten under par with three to play, the New Zealander ended up on a bridge and took a double-bogey six at the short 16th and then made a bogey at the long 18th after playing her wayward down the first fairway.
Australian Minjee Lee, the defending champion, finished birdie, eagle for a 69 and three under par.
But Henderson is the one to catch. She was hailed as a teenage prodigy when she won the 2016 Major as an 18-year-old. But she hasn’t quite lived up to the billing.
With the new putting style – in addition to the technical changes she is leaving the flag in the cup – she now has the form on the greens to match her magnificent ball-striking.
© Agence France-Presse