While most 15-year-olds are dealing with puberty, Atthaya Thitikul is already coping with pressure that comes from global media attention.

The Thai, who in July last year won the Ladies European Thailand Championship to become the youngest known winner of a professional golf tour event, showed her pedigree by taking the lead after yesterday's opening round of the inaugural Women's Amateur Asia-Pacific championship.

She fired eight birdies against two bogeys for a six-under 65 at the Sentosa Golf Club's New Tanjong Course to top the 83-player field. Japan's Yaka Yasuda was second on 66 while Callista Chen, tied for 24th after a 72, was the highest-placed Singaporean.

The winner will earn invitations to the Women's British Open, the ANA Inspiration and next week's HSBC Women's World Championship at Sentosa.

Atthaya's poise extended beyond the ropes. When asked if she ever gets nervous during competitions, Atthaya - "or you can call me Jean-O" - replied confidently in English despite being more comfortable in Thai: "No, I just hit it."

She misjudged her approach on the 12th hole and three-putted the ninth, both par-fours, for her two bogeys which prevented her from registering a personal best eight-under score.

But Atthaya, who only reached a scratch handicap in 2016, was unperturbed by those "mistakes" and added: "I'm happy with my result because my putts, driver and chips... everything was so good."

So too her form since that historic win in Pattaya last year. She was 14 years and four months old, breaking the record for the youngest winner, held by Brooke Henderson (14 years, nine months when she won the Canadian Women's Open). The 20-year-old Canadian is world No. 14 and has won five LPGA Tour titles.

Atthaya, who turned 15 on Tuesday, followed that with victory in the women's singles and team event at the Kuala Lumpur SEA Games last August and then made the cut at the Evian Championship, last year's final Major.

"All these make me more confident and positive to play in different tournaments," she said.

It has been a meteoric rise for Atthaya, who picked up the sport when she was six after deciding to pick golf over tennis. She said: "My family do not play golf... I watched golf on TV and I liked it."

While she hopes to emulate compatriot and former world No. 1 Ariya Jutanugarn, her focus for now is this week's event and a podium finish at August's Asian Games.

Yaka, 17, was also occupied with the present. She said: "I only missed two greens today, so it was a very comfortable round. I started well today and it's good to finish just one behind the leader, so I'm looking forward to tomorrow."