Padraig Harrington has claimed the clubhouse lead at the Wachovia Championship after a flawless opening round at the Quail Hollow Club in North Carolina.

The Dubliner, making his first appearance since the Masters,  is one clear of the field following a first round of 66 in which he didn't drop a shot.

Harrington, who started on the 10th tee, moved into contention with a run of three successive birdies from the 14th to the 16th to reach the turn in 33 shots before picking up another three strokes on the way home to finish on six-under.

Harrington's exploits were not matched by Darren Clarke who is facing an uphill struggle to avoid missing a fifth successive cut. Clarke, who has plummeted down the world rankings as he fights to find some form, failed to make an impact and a four over par round of 76 leaves him well off the pace.

World number one Tiger Woods, who like Harrington has been out of action since the Masters three weeks ago, was among the later starters and is level par after just two holes.

American Jason Bohn, Harrington's playing partner, is alone in second place with South African Trevor Immelman and Swede Carl Pettersson a further shot back after carding 68s. Big-hitting American JB Holmes and Camilo Villegas of Colombia are among a group of six bunched on 69.

World number 11 Harrington, who needed only 24 putts, made a big impression on Bohn.

"It was my first time playing with Padraig and he's an incredible guy," the American told reporters.  "These leaders in the game, you can kind of see why they're so good because their attitude is phenomenal, whether playing good or bad.

"I kind of rode Padraig's coat tails today," added Bohn, whose only PGA Tour victory came at the 2005 BC Open. "He got off to a pretty quick start and played beautiful golf. He made a lot of putts. He's rolling his golf ball really well."

World number two Jim Furyk, who won last year's title after beating Immelman in a playoff, opened with a 71 to finish level with Spaniard Sergio Garcia.