South Korean Ilhee Lee tied the tournament record with a bogey-free round and holds the first-round lead at the Sime Darby LPGA Malaysia.
In sweltering conditions, Lee fired a 7-under 64 to establish a one-shot lead over Brittany Lang. Paula Cremer, Jodi Ewart Shadoff and Eun-Hee Ji were two shots back with a first-round 66.
"My goal was 3-under par every day this week, so I feel like I'm OK for the next couple of days," Lee said.
Top-ranked Inbee Park shot a 70, good for 28th after the opening round. Park made a furious rally on the final day to win the tournament in 2012.
Lee's seven-birdie performance bested her low round of the year by three strokes.
Lang birdied six times in her first nine holes. But she bogied her final hole to fall a shot off the lead. She's solo in second place with her back-nine 30 giving her a 65.
The twosome tees off at 9:56 a.m. local time Friday.
The Sime Darby LPGA Malaysia is the second tournament in a five-event swing that goes through Taiwan, Japan and South Korea.