South Korea's Kim Soo-bin fired a course record nine-under par 63 to lead the LPGA-sanctioned Australian Women's Open at The Grange here Thursday. The Canada-based Kim carved three shots off the previous best round by a woman on the West Course to lead the tournament by three shots. While Kim was blazing around the course with nine birdies, world No.1 Lydia Ko carded a two-under 70 to begin her title defence. The New Zealander was just 17 when she became the youngest player to win the title in Melbourne last February, her first tournament win after topping the rankings. "I'll take it," Ko said. "I hit two really loose shots where it was hard to put myself in position the next time, but overall I played pretty solid. "Not many putts dropped but they were hitting the edges. I think I was putting a good stroke on it and that's all you can do." But the first round was all about Kim, 22, who is ranked 256th in the world. Kim said her putter was hot. She had just 26 putts for the day and hit 16 of the 18 greens in regulation. "I was just picking my line and rolling them in, let the ball do the rest," Kim said. "My coach (Brian Jung) was joking around and saying ‘let's make 20 birdies this week', and I said ‘yeah, I like that idea, let's keep it rolling'." It was Kim's first tournament round of the year after a long off-season, and her ranking did not get her into the field for the first two LPGA Tour events of the season. American Casey Grice and German Caroline Masson were in joint second place on six-under 66, with five players at five under, including Australia's five-time champion Karrie Webb and 1996 champion Catriona Matthew of Scotland. Webb's round included six birdies, one of which, at the par-four sixth, she counted as spectacular. Stuck behind trees, she swerved the ball up to four metres and then rolled the putt in for a three. "I probably made the best birdie of my career on six," she said. Willett in hot chase England's fast-rising Danny Willett knocked in three birdies and an eagle over his final six holes to pull to within a stroke of the opening-round lead at the Maybank Championship Malaysia Thursday. Willett, who has leapt up golf's world rankings thanks to a run of strong outings including a win in Dubai two weeks ago, shot a six-under 65 in the new tournament's debut despite a slow start. Nathan Holman, a 24-year-old from Melbourne who won the Australian PGA Championship in December, was in sole possession of the lead with a bogey-free 64 in steam-bath conditions at the par-71 Royal Selangor Golf Club. Willett was joined at 65 by six other golfers on a crowded leaderboard. Besides his Dubai Desert Classic victory, the fourth win of his career, the European Ryder Cup hopeful has logged a handful of other top-10 finishes in recent months and quickly become one of golf's young players to watch. He has soared from 47th a year ago to world number 13 today and is the top-ranked player in the Malaysian tournament, which also features Major champions Louis Oosthuizen and Martin Kaymer. The $3 million tournament, co-sanctioned by the European and Asian Tours, is the successor to the longtime Malaysian Open, which has been discontinued due to a sponsorship shift.