Tiger Woods seized the first-round lead at the 91st PGA Championship on Thursday, using deadly driving accuracy and sharp putting for his best major round since returning from knee surgery.

Woods fired a five-under par 67 to grab a one-stroke edge over defending champion and playing partner Padraig Harrington of Ireland after 18 holes and humble 7 674-yard Hazeltine, the longest course in major golf history.

"I'm very comfortable with how I'm playing," Woods said. "I hit the ball well pretty much all day. I hit a lot of good putts. They were hitting the edge and staying out. This round could have been a really low number."

Woods hit 12 of 14 fairways to equal his best PGA Championship performance and sank five birdies in a bogey-free round on a course where he settled for second in the 2002 PGA Championship despite birdies on the last four holes.

Woods, who missed the cut at last month's British Open and shared sixth at the Masters and US Open, has won five times since returning from knee surgery in February, including tuneup events the past two weeks.

But this will be the first year since 2004 without a major title for Woods if he fails to lift the Wanamaker Trophy on Sunday.

"I've got to keep plodding along. I just have to be consistent," Woods said. "There are times I've got it together and had some comfortable margins of victory. When I put it together, I don't make many mistakes."

World number one Woods, seeking a 15th major title to move three shy of the career record set by Jack Nicklaus, also could match Nicklaus and Walter Hagen for the all-time record for PGA Championship crowns with his fifth.

Harrington's 68 was one stroke ahead of Australians Robert Allenby and Mathew Goggin, Americans Hunter Mahan and David Toms, Spain's Alvaro Quiros and Fiji's Vijay Singh.

Singh, a two-time PGA Championship winner, matched Toms as low man in the afternoon, when winds and harder greens made scoring more difficult.

"I played well and made a few putts," Singh said. "I've worked really hard the past month and it's all coming together."

World number two Phil Mickelson, in his first major since his wife and mother began breast cancer treatments, fired a 74.

"I had a terrible day putting. I haven't putted this bad in a long time," Mickelson said. "I felt it should have been somewhere in the mid- to high-60s. If I don't throw away those little 3-footers, I'm a few under par."

But the focus was upon Woods, who has won six of eight times when shooting 67 or better in the first round of a major.

"He's the best in the world so we expect him to win. He should," said Allenby, who last won a US event in 2001. "But it's three more days to go and a lot can happen. He's the best but there are a lot of good golfers behind him."

"He puts a little more pressure on you," Harrington said. "You feel like you might as well go for it. You can't hang back."

Woods began at the 10th tee and birdied the par-4 12th from 20 feet and the par-5 15th from inches, sank back-to-back birdies at the par-4 second from 20 feet and par-5 third from 30 feet and had a tap-in birdie at the par-5 seventh.

"We didn't play anywhere near it's full length," Woods said. "The way the course is set up, you can be aggressive, make a few more birdies going at the flags."

Woods, who had his first first bogey-free start in a major since the 2000 British and US Opens that he went on to win, has 70 career titles, 12 shy of Sam Snead's all-time mark.

"He's number one in our sport and he has been for a while and he probably will be for a lot longer," Northern Ireland's Rory McIlroy said after a 71. "I'm just going to keep as close to him as possible and see what happens."

Quiros birdied four of his first eight holes and showed Woods that he would be a threat by reaching the green at the 606-yard par-5 11th in two shots - the second with a driver - while Woods and his group were putting.

"He apologized," Woods said. "Nothing to apologize for. It was phenomenal."

Thailand's Thongchai Jaidee recovered from back-to-back bogeys to end the front nine by starting the back side with three birdies in a row, then added another birdie at the par-5 15th to finish with an opening round 70.

"I played very well, very good comeback on the back nine," Thongchai said.

Also in the group at 70 was England's Lee Westwood, who was third at last month's British Open and last year's US Open.

"I keep having these close calls and continually proving to myself that my game is improved and I'm good enough to win one of the majors," Westwood said.

Spain's Sergio Garcia, seeking his first major title, was on 71.

"I didn't too many mistakes but still a lot of work to do," Garcia said.