South Korea's Na Yeon Choi obliterated the field with a stunning seven-under-par 65 to surge six shots clear in Saturday's third round of the U.S. Women's Open in Kohler, Wisconsin.
On a breezy day with tricky hole locations at Blackwolf Run where only four other sub-par scores were recorded, Choi put herself in prime position to win her first major title.
The 24-year-old Korean, who has triumphed five times on the LPGA Tour, seized control of the tournament in masterly fashion with eight birdies and a sole bogey to finish at eight-under 208.
''I couldn't believe how I got eight birdies today,'' Choi said. ''But I did. And I'm very happy, and I'm very satisfied and I'm very excited.''
Choi's 65 was the 11th carded at a U.S. Women's Open where only four lower rounds have ever been posted.
Compatriot Amy Yang was alone in second after carding a 69, the next-best score of the day, with American teenager Lexi Thompson (72), Japan's Mika Miyazato (73) and Germany's Sandra Gal (74) a further stroke back at one-under 215.
Canadians Lorie Kane of Charlottetown and Sue Kim of Langley, B.C., are well off the pace after rounds of 82 and 85 respectively.
Michelle Wie faded, shooting a 6-over 78 to fall to 2 over. Wie shot a 66 on Friday, putting her a stroke behind leader Suzann Pettersen of Norway.
Pettersen endured a difficult day, battling to a 78 that included a pair of double-bogeys to finish a distant nine strokes off the pace.
Pettersen, who had led by one shot after the second round, briefly doubled her advantage when she birdied the par-five second.
However, she fell back into a tie for the lead with the first of her double-bogeys, at the par-four third, before Choi took control with a sizzling birdie display.
The petite Korean scorched the front nine in four-under 32 and then picked up further shots at the 10th, 11th and 12th to charge five shots clear at eight under.
Though she ran up a three-putt bogey at the tricky par-three 13th, Choi recovered with another birdie at the 17th to stretch her lead to six.
Top-ranked Yani Tseng struggled, shooting a 78 and fading to 8 over.
Tseng said she had trouble feeling comfortable with her club selection at times as she tried to deal with the wind and tough pin placements.
And Tseng said she didn't see too many opportunities for low scores out there, adding, ''Except Na Yeon.''
Since turning professional in late 2004, Choi has established herself as one of the leading players on the LPGA Tour.
In 2010, she won twice on the U.S. circuit before ending the year by clinching the money list title and also the prestigious Vare Trophy for the lowest scoring average, with 69.8.
Choi has yet to win a major title, but this week offers a golden opportunity to change that.
The lowest round in U.S. Women's Open history was a 63 by Helen Alfredsson in 1994. Three other players have shot a 64 in the Open.