American Stacey Lewis and Australian Kristie Smith each shot 7-under-par 65s to take a share of the second-round lead at the Australian Ladies Masters on Friday.

Lewis and Smith were at 12-under 132 after 36 holes at Royal Pines. Yani Tseng of Taiwan shot 66 and was a stroke behind.

Six players were tied for fourth, two strokes back: Germany's Sandra Gal (64), American Ryann O'Toole and South Africa's Ashleigh Simon (66s), Ahn Shin-ae of South Korea and England's Melissa Reid (67s) and Maria Hernandez of Spain (68).

English veteran Laura Davies shot 67 and was at 136, four behind. Seven-time winner Karrie Webb shot 71 and was five behind.

Lewis had two top-three finishes in the United States last year. She plays with a steel rod and five pins and screws in her back after having surgery for scoliosis three years ago. She had 10 birdies and an eagle in 36 holes.

The best round of the day belonged to another American, Mollie Fankhauser, who had nine birdies on her way to a round of 63.

Tseng thought she could have done better than her 66.

"I feel like I should have shot 10 under," Tseng said. "I don't know if it was my stroke or my head. It was very stressful."