Japan's Momoko Ueda made six birdies on the back nine in an 8-under 64 to take a three-stroke lead after the second round of the LPGA Tour's Mizuno Classic on Saturday.
Ueda, who won this event in 2007, made her fourth straight birdie on the par-4 18th when she chipped in from the edge of the green to finish at 13-under 131.
"I think I did a good job and it wasn't hard today," said Ueda, whose Mizuno Classic win in 2007 earned her LPGA membership in 2008. "But I was surprised to get that birdie on the 18th hole."
Japan's Sakura Yokomine was three strokes back after a course record 9-under 63 at the Kintetsu Kashikojima Country Club.
Second-year LPGA Tour member Mina Harigae of the United States shot a 5-under 67 and was tied for third with Japan's Mayu Hattori and China's Shanshan Feng at 9-under 135.
The 25-year-old Ueda, who has eight career wins on the Japan Tour, made her sixth birdie of the day on the par-5 16th when her approach landed 4 feet from the hole. She then made a 10-foot birdie putt on 17 to go to 12 under.
"Today was different even from the times that I have played good golf," said Ueda, who started the day one stroke off the lead. "It felt natural and relaxed."
Defending champion Jiyai Shin of South Korea shot a 71 and was tied for 26th at 4 under. Stacy Lewis of the United States was tied for 18th after a 71.
Harigae, the LPGA Futures Tour's 2009 Player of the Year, put herself in position to win her first LPGA Tour title.
"I was a little nervous and my drives weren't as good as yesterday, but my putting kept me going," said Harigae, who recorded seven birdies and two bogeys. "I'm glad I got used to playing in front of a big crowd today with Momoko so I'll be used to it in Sunday's final round."
The Mizuno Classic is co-sanctioned by the LPGA Tour and Japan LPGA Tour. Sunday's winner will take home $180,000.