So much for the Tiger Woods theory of separation.

After two rounds of torrid scoring at the Augusta National Golf Club, Woods speculated that the tightly cropped leaderboard would loosen up once the course conditions firmed up. He also predicted the cream of the field would rise to the top.

He was half right. If anything, the leaderboard only got more crowded in time for the final round -- in quality if not in quantity. Twelve players are within five shots of Woods' lead at 12-under 204 -- and that 12 includes Phil Mickelson at 205, Mark Calcavecchia and Chris DiMarco at 206 and David Duval and Ernie Els at 207.

The only degree of separation came from Woods, who birdied 13, 14 and 15 to grab his one-shot lead over Mickelson heading into today's play.

It's familiar territory for Woods, who has won 20 of his 26 career PGA Tour victories as a final-round front-runner. Only twice has he ever lost a lead in the final round -- to Ed Fiori at the 1996 Quad Cities Classic and to Mickelson at the 2000 Tour Championship.

Mickelson's victory at East Lake in Atlanta snapped Woods' streak of 19 consecutive victories when leading or tied after three rounds. One of those 19, of course, was Woods' 12-shot triumph at the 1997 Masters.

All Woods needed to do to secure the top spot for Sunday was not blow up. He plodded along with six consecutive opening pars before breaking through for birdie on No. 7. Then he careened through Amen Corner and beyond at birdie-bogey-birdie-birdie-birdie.

"I didn't really do anything great," Woods said. "I just didn't really try to do anything special. Just tried to put the ball in play there, put it on the green, make a putt if I could. If I didn't, just two-putt and move on."

Woods, whose worldwide record when leading entering the final round is 24-4, inherited the outright lead on the par-5 15th with his last birdie of the day. Thanks to Angel Cabrera's double-bogey on the same hole two groups in front that dropped him to 10-under, Woods and playing partner DiMarco went into No. 15 tied at 11-under. Woods got up-and-down for birdie, and DiMarco bogeyed to leave Woods all alone.

"I understand what the danger is out there," Woods said. "I understand that you have to execute the golf shots. If you slip up just a little bit, it can be a marginal shot, anything can happen."

Unless the wind blows and the course conditions toughen dramatically, Woods understands the frailty of his position -- even if he is the undisputed No. 1 player in the world.

"I know that there are a lot of other good players at the top of the leaderboard who have a wonderful chance of winning [Sunday] if they just play a good, solid round. So I'm going to go out there with the intent of just trying to keep the ball in play and put it on the green so I have, hopefully, some uphill putts."