Michael Thompson shot 4-under-par 66 Thursday for the early lead at the U.S. Open in San Francisco. Thompson, playing in just his third major tournament and first since 2008, was 2-over after six holes but had six birdies the rest of the way, including on the 18th hole. He was among the early tee times Thursday morning but by the time he finished -- around 3:40 p.m. EDT -- only two other golfers were under par for the day. One of those was Tiger Woods who played a relatively steady round with three birdies and two bogeys. Two of his birdies came at Nos. 4 and 5 -- his 14th and 15th Thursday -- for a 1-under 69. David Toms was also at 1-under with two holes to play after three birdies and a pair of bogeys. One of his bogeys came at the sixth hole, which was his 16th of the round. The second set of tee times began at 3:30 p.m. EDT. Among the featured groups in the afternoon was one with Luke Donald, defending champion Rory McIlroy and Lee Westwood, who are the top three ranked players in the world. The morning\'s key group was the one with Woods, Phil Mickelson and Masters champ Bubba Watson but only Woods lived up to the hype as Mickelson turned in a 6-over 76 and Watson shot 78.