Japan’s Ai Miyazato fired a six-under 66 for the first-round lead at the LPGA Safeway Classic at Pumpkin Ridge Golf Club.
Miyazato had a one-stroke lead on Taiwan’s Teresa Lu and Jee Young Lee of South Korea.
Miyazato is in a five-way tussle for the world’s top ranking with American Cristie Kerr, Jiyai Shin of South Korea, Suzann Pettersen of Norway and Yani Tseng of Taiwan.
Since the retirement of Lorena Ochoa earlier this year, Miyazato, Kerr and Shin have traded the top ranking six times in the past three months.
"Even though it was just for two weeks, I was so very happy," Miyazato said about being number one.