No. 1-ranked Lydia Ko of New Zealand, helped by a chip-in eagle, took a share of the second-round lead Friday with South Korea's Jang Ha-na and Ariya Jutanugarn of Thailand at the Women's Australian Open at Royal Melbourne.

The 17-year-old South Korean-born Ko, playing her second tournament since becoming the youngest golfer, male or female, to earn the top ranking, shot a three-under 70 while Jang finished with a 69 and Jutanugarn a 71, giving the leaders 36-hole totals of 6-under 140.

England's Charley Hull, the Ladies European Tour's top money winner last year, was in fourth place after a 71, two strokes behind.

American Jessica Korda, the 2012 champion at Royal Melbourne, shot 71 and was in fifth place, three strokes off the lead.