Yuka Saso needed 32 putts on her way to a one-under-par 71 and slid to joint 15th in the Honda LPGA Thailand at the Siam Country Club in Chonburi, Thailand Saturday.

The 20-year-old Filipino-Japanese made only two birdies against one bogey to complete 54 holes on 10-under 206, 10 shots behind Thai rookie Natthakritta Vongtaveelap who sizzled for 64.

Saso reached the turn on 2-under after birdies on 1 and 6 but made a bogey on 17 to fall into the same group with Hye-Jin Choi, Allison Lee, Cheyenne Knight, and Jodi Ewart Shadoff.

Vongtaveelap, who entered the tournament on sponsor's exemption, opened with an eagle and collected six birdies in a bogey-free round. She used her putter only 25 times to get to 20-under 196 as she built a four-shot lead over compatriot Atthaya Thitikul who also had a 64.

Alone on 201 was Celine Boutier who fired a 67 built around six birdies against a single bogey.

Tied for fourth on 202 were Lilia Vu (66), Anna Nordqvist (67), and Maja Stark (69).

The leading scores:

196 — Natthakritta Vongtaveelap (67-65-64)
200 — Atthaya Thitikul (67-69-64)
201 — Celine Boutier (68-66-67)
202 — Lilia Vu (66-70-66), Anna Nordqvist (65-70-67), Maja Stark (66-67-69)
203 — Ashleigh Buhai (72-65-66), Hyu Joo Kim 67-70-66, Lydia Ko (68-68-67), Nelly Korda (68-66-69)
205 — Maria Fassi (72-66-67), Charley Hull (69-67-69), Pornanong Phatlum (70-65-70), Georgia Hall (67-68-70)
206 — Hye-Jin Choi (69-71-66), Allison Lee (68-72-66), Cheyenne Knight (70-68-68), Jodie Ewart Shadoff (69-66-71), Yuka Saso (67-68-71).