Vance Veazey is alone in second place at 8-under-par 64, followed by last week's St. Jude Classic winner David Toms, who is in third place after a 7-under 65.
There was a weather delay that lasted nearly two hours Thursday. All players returned to the course and were able to complete their opening rounds.
Woods got his round started on the back nine at Cog Hill and wasted little time in breaking into red numbers. At the par-5 11th, Woods knocked a 6-iron onto the putting surface with his second shot and rolled home a 30-footer for eagle.
He quickly gave a stroke back with a three-putt bogey at No. 12, but birdied the 13th when he once again used a 6-iron to get the ball to finish 12 feet from the hole.
Woods tallied back-to-back birdies at 15 and 16 when he two-putted from 40 feet at the par-5 15th and rolled home a 15-footer at No. 16. After the stoppage, Woods hit a terrible 8-iron at the 18th that landed right of the green. His chip was nothing special either as he went over the green, but the two-time former Western Open champion chipped in his par save.
'When you're right in the middle of the fairway, to hit that poor a golf shot, especially when I know I wasn't committed to playing the golf shot, that to me is so frustrating,' said Woods 'It was kind of in the back of my mind should I hit the other club instead of saying pick a spot out there and rip it. I didn't do it and it was nice to get away with that.'
Woods coasted on the second nine after the lucky save at 18. He birdied No. 1 then parred the next three holes before another birdie tear at the end of his round.
The No. 1 player in the world reached the green in two at the par-5 fifth and two-putted from 30 feet. At the par-3 sixth, Woods played a 6-iron to 12 feet and holed the putt before a tap-in birdie at the next hole. Woods closed his round with a two-putt birdie at the ninth for his lowest round of 2003.
'I hit a lot of good shots today,' said Woods. 'It's a lot of fun when you hit shots that flush and that solid and it's awfully nice to get rewarded by making some putts. I hit some good putts with some nice speed that went right in the hole. It was a good combination.'
Woods has been hearing talks of a recent slump. He's failed to contend at either major tournament so far this season and has not won since Bay Hill in March, but insisted that he took no satisfaction out of possibly squelching slump rumors.
'It's certainly not because of that. It's because of the fact that the things that I've been working on came together today. That's what you have to keep in mind.'
Veazey mixed nine birdies and one bogey on Thursday in what was clearly his best round of the season. He opened the season with a tie for 40th at the Sony Open in Hawaii, but missed every cut on tour before a share for 20th last week in Memphis.
'It has been a tough year so far,' said Veazey. 'The main thing I want to do is keep plugging away. I felt like last week my game was starting to come together and I played solid rounds. I shot under par four days, every day.'
Toms posted one bogey, at the fourth, and closed with three birdies over his last four holes as he tries to join Kenny Perry and Ernie Els as players to win in consecutive weeks on tour in 2003.
'I can use the positive in that last week I played great and I won the tournament and take confidence away from that, but here it's a totally different course,' said Toms, who won the 2001 PGA Championship. 'The greens are totally different, the fairways are totally different, just a different style of golf.'
Defending champion Jerry Kelly carded an opening-round 66 for fourth place. Masters champion Mike Weir, Cliff Kresge, Jason Gore, Chad Campbell, Heath Slocum and Brian Bateman are tied for fifth place at 5-under-par 67.