Australia's Gabriela Ruffels made a strong start but Japan's Akai Iwai stole the show in the opening round of the LPGA Tour's tournament in Pattaya, Thailand.
Playing on a sponsor's invitation, Iwai shot a flawless 10-under 62 with 10 birdies to lead by three shots from Sweden's Maja Stark with Thailand's Moriya Jutanugarn a further shot back.
Ruffels was six under through her first 10 hopes at Siam Country Club's Pattaya Old Course before two bogeys left her with a 68 and a share of seventh place on the leaderboard.