Nasa Hataoka shot a bogey-free, 9-under 63 to share the lead with China's Yin Ruoning after the first round of the U.S. LPGA season-ending Tour Championship on Thursday.
Hataoka, a six-time winner on the tour, made five birdies on the front nine and four more coming home on Tiburon Golf Club's Gold Course in Naples, Florida.
Australia's Minjee Lee and Sweden's Anna Nordqvist were third and fourth, respectively, after rounds of 64 and 65.