Australia’s Karen Lunn is the clubhouse leader with a score of four-under halfway through the first round of the women’s NSW Open at Oatlands golf club.

Lunn, who last week won the Royal Canberra Ladies Classic, came home strongly, picking up three birdies on the back nine on Friday to shoot a 68.

She holds a one-stroke lead over New Zealand prodigy Lydia Ko, France’s Gwladys Nocera and South Korea’s Hae-Rym Kim.

14-year-old Ko, last year’s runner up, showed she had continued to progress over the past 12 months with a confident round which included just one bogey despite windy and rainy conditions.

Pre-tournament favourite Katherine Hull enjoyed the perfect start, picking up three birdies in the first four holes before falling away badly to shoot a one-over 73.

The 29-year-old showed some signs of rust on the greens as she dropped three shots between holes 12 and 17, but remains in a position to make up ground over the weekend.

Welsh veteran Becky Morgan and England’s Melissa Reid both sit two shots back from Lunn at two-under despite both enduring very different days.

Morgan shot into the lead after lighting up the front nine with four birdies, but struggled to repeat the dose on the back nine, while Reid mixed birdies with bogeys throughout the day as she blew out some cobwebs.

The 24-year-old, who has played just one tournament in the past three months, admitted she had a rusty morning before finishing strongly with three birdies in the final six holes.

Rain is falling steadily, with half of the field – including big-hitting Englishwoman Laura Davies – still out on the course.