Woods and Weir set the course record with 65s, while the leaders tied the tourney scoring mark.
MEDINAH, Ill. -- The PGA Championship has rarely looked so easy.
With Tiger Woods atop the leaderboard, winning the final major of the year could still be as hard as ever.
His final birdie Saturday came on the par-3 17th hole, a 12-foot putt that nearly spun out of the side of the cup. Woods was walking to the hole when he stopped, sighed when it dropped, then pointed his finger at the cup as if reminding his golf ball to behave.
It led to a 7-under 65, matching the course record at Medinah.
And it left him tied at the top with British-born Luke Donald, who knows as well as anyone that Woods is 11-0 when he has at least a share of the 54-hole lead in the majors.
"His numbers are obviously impressive and that's why he's the best player in the world," Donald said after his 66. "He knows that just playing his game is going to be good enough, usually."
But this is a new game for Woods.
The notion of par being a good score in the Grand Slam events was laughable at Medinah, where soft greens have allowed Woods, Donald and everyone else to take dead aim at the flag, forcing them to make birdies simply to stay in the hunt.
Both made their share to finish at 14-under 202, matching the record in relation to par for this major. David Toms led at 14-under 196 when he won the PGA Championship five years ago in Atlanta.
"Most majors ... you're just trying to survive and make pars," Woods said. "Tomorrow, I think anyone who wants to win this championship has to make some birdies."
Mike Weir made nine of them and also shot 65, putting him two shots behind at 204.
U.S. Open champion Geoff Ogilvy recovered from a double bogey on his first hole to shoot 68 and was at 11-under 205.
Another shot behind was Sergio Garcia, runner-up to Woods at Medinah seven years ago, and former PGA champion Shaun Micheel.
Whatever the case, all eyes are on Woods.
"It's going to take a low round, because you know Tiger is playing flawless golf," Micheel said. "He's going to be a tough man to catch."
Woods soared into the lead with a string of splendid shots, starting with a 3-iron from 250 yards over Lake Kadijah to 6 feet on the par-3 13th. Then came a bunker shot to 2 feet on the par-5 14th, and a 9-iron from a sand-filled divot to 3 feet on the 15th.
All that went wrong was a three-putt bogey on the next hole, ending his streak of 50 holes at par or better.
But he bounced back with the birdie on the 17th, and Donald matched his birdie with a 6-iron into 4 feet.
"In most major championships, you make pars and sprinkle in a couple of birdies here and there and you're looking pretty good," Woods said. "Today you would have just been run over, which is different."
They still have plenty of company, and some of those faces are familiar.
Weir shared the 54-hole lead with Woods in 1999 at Medinah. Garcia played in the final group with Woods last month at the British Open, won easily by the world's No. 1 player for his 11th major.
Ogilvy spent the first two days matching Woods shot for shot, and the 29-year-old Aussie is not daunted by Woods' record.
"He's not going to win them all," Ogilvy said. "He's pretty special, but he's not unbeatable."
But it all starts with Woods, going for his third straight victory and second straight major title against a fresh face. Donald won his second PGA Tour event in February at the Honda Classic, but has struggled in the Grand Slam events.
"It's going to be a little different. I haven't really contended in a major before," said Donald, who stayed in Chicago after going to Northwestern, where he won the NCAA title in 1999. "This will be a little bit different pressure."
Woods will try to become the first player in the 90-year history of the PGA Championship to win twice on the same course, having captured the Wanamaker Trophy in 1999 by hanging on against Garcia.
This round was full throttle.
Woods and Donald watched the early round on television and saw plenty of birdies, knowing what they had to do.
"It looked like it could be had out there," Woods said. "I felt like I had to go get it."
What might have been great rounds at other majors were just ordinary at soft, vulnerable Medinah.
Masters champion Phil Mickelson cured flaws in his swing and fired at the pins, leaving himself tap-in birdies that carried him into a brief share of the lead through nine holes. But his putter let him down, a flop shot on the 18th didn't reach the green and he had to settle for a 68, leaving him six shots behind.
"It will take a 7- or 8-under-par round to have a chance," he said.
Weir still had a hard time believing he could shoot 65 in a major and pick up only one shot against the leaders. Even more unnerving is chasing Woods, although he's eager for another chance.
"I know everybody's expectations are that he's going to go out and win the championship, because he's done it so many times from the front," Weir said. "But there's always time to stop the streak, so hopefully, I can do it."
The scoring was no surprise.
The air was thick with humidity and heavy clouds hung over Medinah after rain pounded the course overnight. Greens that already were soft and spongy became like Velcro and allowed players to take dead aim at the flag.
"The PGA of America can't control Mother Nature," Weir said. "What can you do? It is what it is. You've got to make some birdies."
Did they ever. Medinah came alive with cheers that resounded from all corners, a far different atmosphere from the groans often heard at a U.S. Open. The pace was so hectic that 10 players were tied for the lead at one point.
But for all the birdies, perhaps the most important putt of the day was for par.
Woods started his round by spraying a 3-wood deep in the trees on the right, and his punch shot clipped branches before settling into thick rough well short of the green. All he could do was pound a wedge 35 feet by the hole.
After studying the line halfway between the ball and his hole, his par putt dropped on the final turn and Woods slammed his fist. He followed that with a tee shot that never left the flag as it sailed over Lake Kadijah and settled 7 feet away for birdie.
"I was off and running," Woods said.
With so much drama, about the only aspect to this tournament that turned into a dud was the race for the Ryder Cup team.
Davis Love III was one shot out of the lead, needing eighth place at Medinah to earn a spot on his seventh straight team, and he sure proved himself early. With U.S. captain Tom Lehman watching from across the second green, Love holed a bunker shot for an early share of the lead. He holed another bunker shot for birdie at the fifth to reach 9 under.
But that was as good as it got. Love made too many bogeys, not nearly enough birdies, shot 73 and was in a tie for 18th.
Other Ryder Cup hopefuls also languished.
Stewart Cink shot 73 and Lucas Glover shot 77 to fall out of contention. Barring a big charge from Tim Herron on Sunday, there probably won't be a change in the standings, giving the American team four Ryder Cup rookies.