Lee, seeking her first major title, took full advantage of favourable conditions as she carded eight-under-par, including five birdies in her last seven holes.

The superb display from the world number 32 saw her become the first golfer to shoot a round of 64 at the tournament since 1999.

“The course is perfect now," Lee said.

"The greens are really fast.

“I just try and make par, that's it.

“I think everything was good.

"The driver was good and the irons good. 

"I had a couple missed putts, but not bad."

Cristie Kerr of the United States, winner of the US Women’s Open in 2007, Australia’s Minjee Lee and Amy Yang of South Korea all shot five-under-par but were unable to keep pace with the leader.

Sweden’s Anna Nordqvist, winner of the Women’s PGA Championship in 2009, is among a group of players who are a shot further back, along with American Brittany Lang and Kelly Tan of Malaysia.

As the winds started to pick up and the greens became firmer later in the day, a number of the favourites struggled, with favourite Lydia Ko of New Zealand tied for 52nd place after carding a one-over-par 73.

The world number one, chasing a third major crown, was unable to produce her usual form as she only managed a single birdie on the back nine having been level par halfway through her round.

Brooke Henderson of Canada, the current world number two, also had a tough day out on the course, finishing with a four-over 76.

“I don't know what course she played, maybe the ladies tees, maybe a different course,” said Ko of Lee's round.

“But she played fantastic.

“We were checking the leaderboard, she made two bogeys and still shot eight-under - it's very impressive.

“She must have hit a lot of fairways and made good putts.

“I think obviously that's the key."