Northern Ireland's Darren Clarke fired a six-under-par 66 to take a three-shot lead after the first round of the rain-delayed US Masters at Augusta.
Clarke blazed five birdies and an eagle to keep one-time co-leader Sergio Garcia and American amateur Ricky Barnes at bay.
Spain's Garcia carded a 69, equalled by Barnes with a birdie on 18, as defending champion Tiger Woods, targeting a record third straight Masters title, struggled to an opening 76.
In third, on two under, were Canada's Mike Weir and Zimbabwe's Nick Price.
Woods' campaign began poorly in the overcast but dry conditions as he bogeyed the first, the fourth and the fifth holes for an outward three-over-par 39.
But it could have been worse for the 27-year-old American when he overhit his approach to the par-four fifth.
-6 D Clarke
-3 S Garcia, R Barnes
-2 M Weir, N Price
He chipped his third shot through the green and watched as his fourth dribbled back to his feet before avoiding a double bogey
by chipping in from 35 feet.
The world number one was unable to find any spark after the turn and dropped one more shot on the way home.
Woods' main rival, world number two Ernie Els, found it even more difficult and slumped to a 79.
Phil Mickelson fared better with a one-over 73, the same score as 2000 champion Vijay Singh and former US Open winner Retief Goosen.
Of the other European challengers, former Open champion Paul Lawrie and Masters debutant Justin Rose carded very respectable level-par 72s.
Meanwhile, two-time Masters winner Jose Maria Olazabal kept himself in contention with a solid 73.
Triple winner Nick Faldo went round in 74 and two-time champion Seve Ballesteros signed for a 77.
Rose carded 72 on his Masters debut
Scotland's Colin Montgomerie and Ireland's Padraig Harrington compiled rounds of 78, one shot better than double winner Bernhard Langer, with 1991 champion Ian Woosnam a further shot adrift.
Former champion Sandy Lyle was in the first group out but struggled in the early conditions and compiled a 10-over 82.
Masters legend Jack Nicklaus, a six-time winner, ran up 85, while four-time champion Arnold Palmer, playing in his 49th Masters at the age of 73, signed for a 83. Triple champion Gary Player took 82.
Lyle's playing partner Tommy Aaron, the 1973 champion, carded the worst score of the day of 92.