South Korean Na Yeon Choi leads by two shots after Friday&aposs play at the Sime Darby LPGA Tournament in Malaysia, a day in which Australian Karrie Webb dropped significantly off the pace. Choi and Webb shared the day one lead after shooting rounds of 65 but while the event leader maintained her good form, shooting a four-under 67, her rival slipped down the leaderboard. Webb hit two birdies and two bogeys in an even-par round of 71, which sees her in a tie for seventh with four other players – including compatriot Lindsey Wright – four shots off the pace. Behind Choi, who won the event in 2011, is American Sydnee Michaels while a group of four players are tied for third, three shots behind the leader. Choi started superbly, hitting birdies on holes three, five and six to build some early momentum. Immediately after turning for the back nine she added three more birdies – although they were sandwiched by a bogey on the 11th – and although she would have been disappointed with a late slip on the 17th, she still did enough to claim the outright lead. Michaels fired a six-under 65, including five birdies in a row from holes 11 to 15, to keep the pressure on Choi. Norwegian Suzann Pettersen also did her best to stay in contention with Choi, shooting the day&aposs best score. Pettersen hit seven birdies, four of which came from her final five holes, in a blemish-free round of 64. She is tied with Japanese duo Mika Miyazato and Momoko Ueda and American Lizette Salas at seven under. Ueda and Salas both scored 67 for the day while Miyazato shot a 69. In a five-way tie for seventh are Webb, Wright, Scotland&aposs Catriona Matthew, South Korea&aposs Sun Young Soo and American Paula Creamer. In contrast to her compatriot&aposs performance, Wright played well, shooting a five-under 66.