With conditions at Royal Melbourne set to get even tougher over a hot weekend, world No.1 Lydia Ko looks in prime position to claim a first Australian Open crown.

On a layout much harder than most of those regularly seen on the US LPGA Tour, Ko predicted a final score of 10-under would be a good winning one.

If that proves to be the case, she’s already more than halfway there, having got to six-under, 140 at the halfway stage after back-to-back rounds of 70.

The New Zealander is tied for top spot with South Korea’s Ha Na Jang and Ariya Jutanugarn from Thailand.

England’s Charley Hull is in outright fourth at four under, with Katherine Kirk the leading Australian in a tie for 10th at one under.

Ko is benefiting from the local knowledge offered by her Australian caddy Jason Hamilton and the sage advice of master coach David Leadbetter.

“Having played these kind of sandbelt courses before as an amateur is definitely helping me to play when we come over here,” she said.

“We definitely don’t get any of these kind of courses over in the States.

“I think every course is special in a way but, especially out here, it makes you think a little bit more and try and be smart.

“I was talking to David Leadbetter yesterday and he was like ‘OK Lydia, play smart’, and I think that’s the big key around here.”

The temperature is expected to reach 34 degrees on Saturday and Sunday in Melbourne, which will further harden up the slick greens.