KAPOLEI, Hawaii, April 17, 2013 (AFP) - Ariya hit six birdies in her first nine holes, her only miscue of the day a bogey at the par-four 10th. But she bounced back with an eagle at the par-five 14th, where she drained a 20-footer.
"I had a really good front nine, but I just wanted to make more birdies," said the 17-year-old, who was hoping to beat her personal best of eight-under for a round.
"When I have bogey on number 10 I feel not very confident with my putting. So when I have eagle it made me more confident."
Ariya, a rookie on the Ladies European Tour this season, won her first professional title at the LET tournament in Morocco last month.
She qualified for this week's tournament at Ko Olina Golf Club by winning a qualifier on Sunday.
"I was very confident today," said Ariya, who was in contention for an LPGA tour title in her native Thailand in February only to surrender a two-stroke lead at the final hole in a tournament won by South Korea's Park In-Bee.
She had a one-shot lead Wednesday over Norway's Suzann Pettersen and South Korean Seo Hee-Kyung. South Korea's Kim Hyo-Joo and American Danielle Kang were a shot further adrift on 66.
Kim played in a group with Ariya and 15-year-old New Zealand sensation Lydia Ko, who has yet to turn pro. Ko carded a 71.
"It was very fun because everybody is young," Ariya said of the group. "We're friends. I've played with them before."
Pettersen teed off on 10 and made five of her nine birdies on her second nine.
Already a winner on the Ladies European Tour this season, Pettersen said she wanted to be aggressive -- especially after her equal third place finish in the Kraft Nabisco Championship won by Park.
"My dad was so disappointed after the Kraft that I left all the putts short," she said.
South Korea's Park, newly installed as the world number one, carded a 70. Stacy Lewis, who can regain the top ranking this week, shot a 67 while Taiwan's Tseng Ya-ni, who could also move back to the number one spot with a victory this week, carded a 71.
"I think it's good for the tour when players are going back and forth and creating scenarios of if so-and-so wins they could be number one," Lewis said. "I like that.
"It's fun now," she added. "You're checking what Ya-ni is doing, you're checking what In-Bee is doing. I think it's a good thing for the tour."
Leading first-round scores on Wednesday in the US LPGA Lotte Championship (USA unless noted):
64 - Ariya Jutanugarn (THA)
65 - Seo Hee-Kyung (KOR), Suzann Pettersen (NOR)
66 - Danielle Kang, Kim Hyo-Joo (KOR)
67 - Gerina Piller, Stacy Lewis, Ai Miyazato (JPN), Jane Rah, Ryu So-Yeon (KOR), Beatriz Recari (ESP), Jane Park, Rebecca Lee-Bentham (CAN)
68 - Julia Boland (AUS), Kang Hae-Ji (KOR)
69 - Vicky Hurst, Mina Harigae, Brittany Lang, Caroline Hedwall (SWE), Moriya Jutanugarn (THA), Park Hee-Young (KOR), Lee Mi-Hyang (KOR), Karrie Webb (AUS), Lizette Salas, Austin Ernst, Mariajo Uribe (COL)