New Zealand's Lydia Ko made her second start as world No. 1 a winning one, shooting a final-round 2-under 71 for a two-stroke victory in the Women's Australian Open over South Korea's Amy Yang.

The South Korean-born Ko finished with a 72-hole total of 9-under 283 on the composite course at Royal Melbourne. Yang shot a final-round 72.

Ariya Jutanugarn of Thailand, who was tied with Ko after three rounds in the LPGA, European Tour and Australian Ladies event, shot a 76 to finish third, five strokes behind Ko.

Defending champion Karrie Webb, who won her fifth Australian Open last year at nearby Victoria Golf Club, shot 71 and finished 10 strokes behind.

Play was suspended for about an hour due to nearby thunderstorms and the threat of lightning.