Nasa Hataoka finished the first round of the NW Arkansas Championship among the seven players tied for second place at 7-under-par 64 on Friday, with Mexico's Gaby Lopez holding a one-shot lead.
While Lopez shot a career-low 63 to take sole possession of the lead at the Pinnacle Country Club, the 19-year-old Hataoka carded eight birdies and had only one blemish on her scorecard, a bogey on the par-5 14th hole.
Hataoka said she had planned to play aggressively in the three-day, 54-hole event and did so, jumping out early and sinking a 23-foot birdie putt on the par-4 fifth. She read the greens with improved accuracy after the turn and made four birdies from No. 15.
"I made my short putts and played a good round," said Hataoka, who is making another bid for her first LPGA Tour victory.
"I was able to improve my long game in the back nine. I hope to hit consistent tee shots again and increase my iron distance tomorrow," she said.
Also for Japan, Ayako Uehara and Harukyo Nomura sat in a tie for 79th at 1-under 70.
Uehara, who only had one birdie, regretted that she was not able to enjoy a birdie-fest like many others in the field, saying "if I don't convert chances I won't score well. I hope to do better tomorrow."
Nomura said missing short putts hurt her score, and mistakes in key situations ruined her rhythm.
"I want to close out at 5-under tomorrow," she said.