Overton opened his three-shot advantage with a 6-under 66 yesterday after three rounds at the Wyndham Championship. He is looking for his first victory on the PGA Tour.

"It's better than being three shots back, but I don't think 18 under's going to win the golf tournament," Overton said. "So we can't go out there (Sunday) and just play bad. We've got to go out there and have a good, solid round of golf."

Billy Mayfair (64), Anders Hansen (68), Carl Pettersson (68) and Tim Petrovic (68) were at 15-under 201, with 2003 winner Shigeki Maruyama (67) and Lucas Glover (66) four strokes behind Overton.

The 24-year-old Overton, holding his first lead of any kind in two years on tour, is in front with rookie Steve Marino and veteran John Huston. He took advantage of late struggles by Craig Kanada to build the largest lead at this course since Maruyama led Brad Faxon by three strokes in 2003.

Overton is trying to avoid dwelling on the prospect of his first title.

"It's a journey where we're trying to get to the point in our golfing career, and we're trying to achieve a level, that top level in the world," he said.

Overton overcame a bogey on his first hole with birdies on seven of his next 11 to take control. He bogeyed No. 13 after a birdie on the previous hole got him to 18 under, but he got the stroke back with a birdie on No. 16.

Still, he wound up with the lead to himself at least partly because of Kanada's blunders. Kanada, who entered the third round one stroke behind the leaders, led for most of the third round before running into trouble on the par-4 No. 16.

He sliced his drive out of bounds, then three-putted his way to a triple-bogey that began his free-fall. He nearly sent his drive on the par-3 17th into the bunker and again three-putted, joining four other players five strokes back.

"I looked up and I was no longer tied for first, first all alone _ that's kind of weird," Overton said. "I was like, 'Jeez, that can't be right. Maybe they messed that up or something.'"

Kanada got off to a hot start when he birdied five of his first seven holes and made three putts from at least 15 feet.

"I'm glad (the triple-bogey) happened today instead of tomorrow," he said. "Overall, it was a great day. Just one hole _ maybe 17 as well. I made a lot of good shots, hit a lot of good putts and made a lot of birdies. If I can just keep making birdies and eliminate the mistakes, the over-par things, tomorrow, then who knows?"

Kanada wasn't the only player to struggle late. Nathan Green briefly threatened to challenge, reaching 16 under with a birdie on No. 12.

Then came trouble: bogeys on the par-4 Nos. 14 and 16 sandwiched a double-bogey on No. 15 that dropped him well off the pace at 12 under.

Huston (72) couldn't keep up with Overton, his playing partner, and finished 12 under. Marino (71) was one stroke better.

After high temperatures and low scores dominated the first two rounds, the Forest Oaks Country Club course seemed to firm up and played slightly tougher than in earlier rounds. Only 35 of the 86 players broke 70 Saturday (40 percent); on Friday, it was 71 of 156 (46 percent).

Mayfair turned in the round of the day. He made the cut by just two strokes but now is within striking distance of his sixth PGA Tour victory and first since 1998. His lone bogey was offset by seven birdies and a hole-in-one on the par-3 No. 8, holing out from 202 yards with a 4-iron.

"That shot is going to cost me a lot of money out there," Mayfair said. "I know the members are all having drinks on me right now."

It was an encouraging round for Mayfair, who came to Greensboro ranked No. 75 on the FedEx Cup points list and seeking a boost before the postseason starts next week.