Singapore Thailand's Chapchai Nirat shot a 6-under 65 today in the completion of the third round of the Singapore Open to take a three-stroke lead. Nirat had a 10-under 203 total. Lam Chih Bing was second. Phil Mickelson finished his third round today with a 66, putting him at 6 under and four shots behind. South African Ernie Els also was four back.