Woods was brilliant on the front nine with five birdies, all from inside 14 feet. At the 13th, Woods converted a 4-foot birdie putt, then ran in a 23-footer for birdie at No. 16.
Woods drove into the right rough at the famous 18th, but got a fortunate bounce when his ball hit a marshal and came straight down. His second landed right of the green and Woods chipped 12 feet past the stick. Woods holed the par save to stay within one of the group in first.
'I had not made a bogey all day so it was nice to end the day without making a bogey,' said Woods, who has not carded a bogey in 60 holes at this tournament. 'Especially on a golf course like this, it's always nice to go around here bogey-free.'
As great as Woods was on Thursday, Mickelson was better.
Mickelson, the reigning Masters champion, wasted little time in breaking into red figures. At the par-5 first, Mickelson came up short and left of the green with his 3-iron second shot, but he chipped to 8 feet and converted the birdie putt.
The lefthander hit driver off the tee at five, then needed a sand-wedge for his approach. He sank the 4-footer for birdie, but dropped a shot at the next hole when the driver let him down. Mickelson drove behind a tree and pitched out. His third stopped 25 feet from the hole and the fourth-ranked player in the world two-putted for bogey.
Mickelson closed out his front nine with a pair of birdies. He birdied the seventh, then reached the green in two at the par-5 eighth. Mickelson two-putted, parred nine and made the turn at 3-under 33.
The second nine did not start off well for Mickelson. His drive at 10 found the right rough, then his 3-wood second shot splashed in the water down the left side. He could not save par from 30 feet, but that would mark the last miscue on the round for the hottest player on tour.
He rebounded from the mistake at 10 with a 25-foot birdie putt at No. 11. Mickelson made it two in a row with a tap-in birdie at 12 and after two pars, the tour's leading money winner caught fire.
Mickelson hit a 9-iron to 6 feet to set up birdie at the 15th. The second in a row came as the result of a monstrous drive at the 372-yard hole. Mickelson blasted out of a greenside bunker to 5 feet and converted the birdie putt to reach 6 under par.
At the 17th, Mickelson hit a lob-wedge to 12 feet for his ninth birdie of the round. He grabbed a share of the lead at the 'Blue Monster,' when his 8-iron approach stopped 6 feet from the hole.
'It's a good start to the tournament,' said Mickelson. 'It's nice to play well, especially when the field is so strong.'
Mickelson is in the middle of a spectacular run of golf. He won the FBR Open in Phoenix and the AT&T Pebble Beach National Pro-Am last month, then played well before running into David Toms in the third round of last week's WGC-Accenture Match Play Championship.
He knows why.
'Being able to drive it a lot longer and a lot straighter has made the difference,' said Mickelson, who ranks 11th in distance on tour. 'The misses have been much better. If I can drive it reasonably straight, it's going long enough now where I have wedges in and it's making a big difference.'
Olazabal, a two-time winner at Augusta, began on the back nine Thursday and tallied three birdies on his front nine. He collected his fourth birdie of the round at No. 1 when he drove in a fairway bunker, laid up with an 8-iron, wedged to 18 feet and drained the birdie putt.
The Spaniard did not hit his approach close on his remaining holes of the second nine, but his flat stick was working. He sank a birdie putt from 12 feet at the fifth, 20 feet at seven, 3 feet at eight and 15 feet at his final hole.
Davis, the medalist at last year's Qualifying School, birdied the first, then hit an 8-iron inside 2 feet for a birdie at the fifth. Davis reached the green in two with a 3-wood at the par-5 eighth and converted the 25-foot eagle putt. He closed out his front nine in style with a chip-in birdie at the ninth.
The Englishman parred his first five holes on the second nine, then hit an 8-iron to 15 feet to set up birdie at the 15th. He ran home a 12-footer for birdie at 16, then recorded his third consecutive birdie at 17 when his lob-wedge approach stopped 4 feet from the hole.
Dawson, playing on a medical exemption this season, recorded five birdies through his first 11 holes. He tallied three birdies in his last four holes, including a 10-footer at No. 18 to join the mix in first.
Billy Andrade, Hunter Mahan, Paul Casey and Joey Snyder III are tied for seventh place at 6-under-par 66.
Retief Goosen, the reigning U.S. Open winner, is part of a group at 5-under-par 67. World No. 1 Vijay Singh, Sergio Garcia and Padraig Harrington are in a logjam in 15th at minus-4.
Craig Parry, who won last year's event when he holed a 6-iron on the first playoff hole to defeat Scott Verplank, began his title defense with a 3-under 69. He is tied for 33rd place.