World number one Tiger Woods fired a seven-under 65 to vault into sole possession of first place after the third round of the PGA Buick Open on Saturday.

Woods' superb round moved him to 17-under 199 and came one day after he shot a brilliant 63 in the second round to move into contention at the Warwick Hills Golf and Country Club.

"Today was a scoring day," Woods said. "I hit it good on the front nine, but the back nine, I hit some loose shots and there was some scrambling and trying to keep pace. Guys were making birdies everywhere."

Woods, a three-time winner this season, has won 15 consecutive tournaments when holding a 54-hole lead. He is also 26 of 27 when going into the final round with the lead.

Michael Letzig is in second at 16-under-par 198 after posting a four-under 68. He finished with a disappointing double bogey on the final hole after blowing a bunker shot.

Second-round leader John Senden carded a 71 and is alone in third.

Matt Bettencourt, who shot 65, and Vaughn Taylor, who fired a 69, are tied for fourth place at 14-under 202.

Australia's Greg Chalmers (69), Charles Warren (68) and Jimmy Walker (69) are one shot adrift at minus-13.

The two-time Buick Open champ Woods started quickly sinking a 14-foot birdie putt on the second hole and registering another birdie on three.

"I hit some good shots there on the front, and I made three (birdies) in a row, but on five I lost my concentration a bit and hit a bad shot, but still made four," said Woods of the US. "Overall, I hit it good on the front nine."

He made it three straight birdies on No. 3 and then made another birdie on seven.

On the par-three 17th, Woods rolled in a 33-foot birdie to join Letzig at 17-under-par.

"Seventeen was a nice putt. I've had that putt before, so I just remember it being actually a little bit faster than it looks," Woods said.

"Even though it's straight up the mound, for some reason it rolls up pretty good. So I didn't hit it quite as hard as it looked, but it worked out."

Senden made parr on a half dozen consecutive holes but made birdie on eight and 11.

Letzig, 29, is seeking his first win on the Tour this season. He nailed an 18-foot birdie on No. 14 to take a one stroke lead.