Darren Clarke saw a three-shot first-round lead wiped out as Tiger Woods battled to keep his quest for an unprecedented third straight Masters title on track.

Clarke carded a superb six-under-par 66 at Augusta National, three ahead of Ryder Cup team-mate Sergio Garcia and a massive 10 shots clear of defending champion Woods, who struggled to a 76.

But the Ulsterman could not repeat his brilliant form when the second round started an hour later, ending the day two shots off the lead held by Canada's Mike Weir.

Hampshire's Justin Rose, playing his first US Masters, was on the leaderboard for much of the day, although he was slightly higher than he should have been after the scorers on the first hole mistook him for playing partner Adam Scott.

Rose was credited with Scott's par-four instead of the bogey-five caused by finding a greenside bunker, but was still happy with his opening-round 73 at Augusta.

"It's a pretty decent round here for the first time," said the 22-year-old from Hook, who remained one-over after 10 holes of his second round. "We were working pretty hard out there but I really enjoyed the atmosphere."

Weir's opening 70 made him one of only seven players to break par on the saturated course in the first round, and the left-hander finished strongly to take over from Clarke at the top of the leaderboard.

Birdies at the second and third took Weir to six-under-par with six holes of his second round to play before the siren sounded at 7.26pm local time.

In contrast, Clarke finished with back-to-back bogeys on the ninth and 10th to lie four-under-par, two shots ahead of Phil Mickelson with US Amateur Champion Ricky Barnes another shot back.

Woods was on the second tee, his 11th hole, when play was called off.