South Korea's Lee6 Jeongeun equalled the lowest score ever in a major golf championship with a second round 61, but she still had a couple of Thai golfers snapping at her heels at the halfway stage of the Evian Championship on Friday.

Lee6 had posted her flawless 10 birdie round for a 15 under par 127 total before some of the field had even started their second rounds.

"I knew I needed to make birdie at the last to tie the record," she said. "It's absolutely amazing."

Joint overnight leader, Pajaree Anannarukarn, pecked away at the lead and repeated her opening 65 while Ariya Jutanugarn bolstered the strong Thai threat with a 63.

They shared second place, three behind on 12 under par.

On another day of perfect weather, New Zealand's Lydia Ko, the 2015 champion, continued her back-to-form season with a 65 and was in fourth place with teenage American Yealimi Noh (68) on nine under par.

Lee6, the 2019 US Women's Open Champion, matched the 10 under par 61 set by compatriot Kim Hyo Joo at the same venue in 2014.

She started on the back nine and reached the turn in 32 with birdies at the 11th, 12th, 17th and 18th.

The 25 year-old's second nine was even better. Birdies at the first and fourth were followed by four in a row from sixth for a memorable inward 29.

She chipped in at the eighth to set up final hole drama - and a 15 foot birdie putt at the long ninth sealed the deal.

- 'Didn't feel my best' -

"I actually didn't feel my best. My swing is still not perfect. But I had a lot of birdie chances and my putting was really, really good," she added.

"I felt great after the first nine and I knew I could make more birdie chances on the back. At the short eighth I missed the green with my six iron, but then the chip in was amazing.

"After No. 6 I knew I needed three more birdies for the record and two holes are par 5s. But the chip in was really lucky."

Remarkably, the 61 wasn't the lowest score of Lee6's career. She has shot 60 in Korea - another record.

Kim set her score in the first round seven years ago and went on to win the title. She also has a chance of a second Evan title after a second round 68 for seven under par.

Lee6 added the number to her surname because there were already five Lee Jeongeuns on the LPGA Tour when she joined in 2017.

Pajaree highlighted her second round with an eagle at the long ninth and she also had six birdies to raise hopes that a first LPA title could come in a major wrapping.

"I am really pleased with the score," she said.

"Majors are special and I just hope I can keep it going over the weekend."

Ariya Jutanugarn, who became the first Thai golfer to win a major at the 2016 Women's British Open and also won the 2018 US Women's Open, eagled the long ninth - her final hole - with a 20 foot putt.

"I watched Jeongeun on the TV before I went out and she was incredible," said the former world number one.

"I just went out to shoot as low as possible and was really lucky to finish with an eagle."

Current world number one Nelly Korda had a fraught day battling to make the cut.

But she made it with a couple of shots to spare by adding a 67 to her opening 74.

Defending champion Ko Jin-young, from South Korea, also finished on one under after a 69.