(AP) Thailand's Pornanong Phatlum shot an 8-under 64 on Thursday to take a one-stroke lead over Lexi Thompson after the first round of the Safeway Classic.
The 23-year-old Phatlum had 10 birdies and two bogeys in her afternoon round at Columbia Edgewater.
The 18-year-old Thompson eagled the par-5 seventh hole and had five birdies in her bogey-free morning round. She won the 2011 Navistar LPGA Classic for her lone tour title.
Christie Kerr, the winner in 2008 the last time the event was played at Columbia Edgewater, was at 66 along with Lizette Salas and Germany's Sandra Gal.
Second-ranked Stacy Lewis, returning to play after withdrawing from the Canadian Women's Open last week because of illness, opened with a 67. She won the Women's British Open on Aug. 4 at St. Andrews and had consecutive early season victories in Singapore and Phoenix.
Hall of Famers Juli Inkster and Se Ri Pak also were in the large group at 67 that included Michelle Wie, Yani Tseng and Ai Miyazato. The 53-year-old Inkster won the last of her 31 tour titles in 2006.
Natalie Gulbis had a hole-in-one on the second hole and finished with a 68.
Suzann Pettersen, the 2011 winner, also shot 68.
Defending champion Mika Miyazato opened with a 71.
A 72-hole event for the time, the tournament is back at Columbia Edgewater after four years at Pumpkin Ridge.
Top-ranked Inbee Park withdrew Tuesday because of flu-like symptoms.