"I've got to keep it going," Singh said. "I've been playing well for two days for a while now, but I need four days of good playing. Sooner or later, I think four days is going to happen. And hopefully, it starts this week."
Woods started slowly and finished strong, with birdies on his last two holes for a 67. McIlroy, coming off what he called one of the best ball-striking rounds of his life, had to overcome four bogeys for a hard-earned 68. Joining them one shot out of the lead was Ryan Moore, who had a 66 and seems to play well in the BMW Championship no matter which state it is held.
Jiyai Shin followed her opening 9-under 62 with a 68 to take a two-stroke lead in the Kingsmill Championship in Williamsburg, Va.
The South Korean player had four birdies and a bogey to finish two rounds at 12 under on Kingsmill's River Course. She won the last of her eight LPGA Tour titles in November 2010.
American Danielle Kang was second after a 64.
Vijay Singh -13
Ryan Moore -12
Rory McIlroy -12
Tiger Woods -12