Phil Mickelson made the first significant move at the top of the U.S. Masters leader board today, shortly before defending champion Tiger Woods stumbled with a double-bogey six at the par-four third.
Mickelson holed a monster birdie-putt from 60 feet at the 575-yard second to close to within three of Jeff Maggert's lead, and stayed at one under for his round with pars at the next three holes.
The Californian, chasing his first major title on his 43rd start, was tied for fourth at two under, two behind Mike Weir, who also birdied the second.
Mickelson's birdie effort at the second was matched soon after by world number one Woods, who rifled his approach there to 20 feet and two-putted for a birdie-four.
But the world number one, bidding for an unprecedented third consecutive title at Augusta National, then pushed his tee shot on three into the woods and, despite a clever left-handed recovery, duffed his chip on his way to a six.
Woods, four off the pace at the start of the day, then three-putted the par-three fourth to slip back into a tie for 10th at one over.
Vijay Singh, the 2000 champion, also birdied the second to climb to third at three under with twice winner Jose Maria Olazabal, after four holes, 2002 U.S. PGA champion Rick Beem, after seven, and Jim Furyk, after five, were tied for seventh at one under.
Pacesetter Maggert, who equalled Woods's 66 for the low round of the day in yesterday's third round, stayed three clear of the field after rolling in a 10-foot putt for par at the first.