SAN FRANCISCO, USA (AFP) — Michael Thompson seized the clubhouse lead in the first round of the US Open yesterday, with 14-time major champion Tiger Woods nipping at his heels.

Thompson, playing just his second US Open, used his familiarity with the demanding par-70 Olympic Club Lake Course to good advantage, firing seven birdies in a four-under par 66.

Thompson was runner-up at Olympic in the US Amateur Championship in 2007.

Woods, seeking his first major title since his 2008 US Open triumph, carded a one-under 69.

He and US veteran David Toms were Thompson’s nearest rivals in the clubhouse, while on the course Argentina’s Angel Cabrera had thrust himself onto the leaderboard at two-under with back-to-back birdies at the second and third holes.

Woods said the course had firmed up considerably, despite light fog in the morning. By afternoon that had burned away, paving the way for even tougher conditions.

Defending champion Rory McIlroy of Northern Ireland opened with a bogey at the first hole, the imposing 520-yard par-four that used to play as a par-five.

England’s Luke Donald and Lee Westwood, the world’s first- and third-ranked players who are both seeking a first major title, were both three-over through five holes, Westwood opening with a double-bogey at the first.

The afternoon leaderboard took on an international flavour with Japan’s Ryo Ishikawa, Ireland’s Peter Lawrie, Germany’s Martin Kaymer and Northern Ireland’s Graeme McDowell all reaching one-under early in their rounds.