LEONA MAGUIRE battled scorching temperatures and grainy greens, but not even a bogey-free six-under 66 saw her close the gap on the leaders in the Honda LPGA Thailand.

Seven shots off the pace after an opening 70, the Co Cavan star birdied the 10th and 14th at Siam Country Club's Pattaya Old Course to get to four-under, then birdied four of her last six holes by picking up shots at the fourth, fifth, seventh and ninth.

Scores

She moved up 20 spots to tied 22nd on eight-under-par but finds herself eight strokes behind Japan's Naas Hataoka and Australia's Su Oh, who followed opening 63s with seven-under 65s to lead by a shot on 16-under from France's Celine Boutier and Denmark's Nanna Koerstz Madsen, who both posted 64s.

"My approach shots were dialled in and gave myself a lot of chances," Maguire said after missing just two fairways and only three greens. 

"The greens are very grainy and I'm finding it tricky to read. It was also incredibly hot and humid today, so I'm trying to keep the energy levels up and stay patient."

Play was delayed by one hour and 43 minutes due to lightning in the area, but that didn't stop Hataoka or Oh, who were tied for the first-round lead with Germany's Esther Henseleit, from going bogey-free.

Oh birdied three par-fives and two par threes to get to five-under for her round before closing with an eagle three at the 18th, where her approach almost dropped for an albatross before inches away.

"Yeah, lots of tap-ins for the next two days would be great," the Australian said after she tied Hataoka with a new 36-hole tournament record low of 128. 

"I think the scoring, doesn't matter what course we play, someone is going to go low. Like everyone is so good now. "

Hataoka made seven birdies on another blemish-free card and admitted she was just trying to keep up with her playing partner Oh.

"She made birdie a lot, and I'm going to try more birdies together," she said, adding that her gameplan will not change. "Just keep going, yeah. Yeah, I want to make more birdies."

China's Xiyu Lin is solo fifth on 14-under after a 66 with Jennifer Kupcho and Canada's Brooke M. Henderson four behind the leaders on 12-under after 67s.

Minjee Lee shot 64 to join Carlota Ciganda and Alison Lee in a tie for eighth on 11-under as joint overnight leader Henseleit carded a 71 to fall back to tied 11th on 10-under.