SAN FRANCISCO -- Even after 10 matches that stretched over 10 hours in the chill of late summer in San Francisco, what put the Americans on the cusp of another victory in the Presidents Cup were two shots by Tiger Woods.
First came a 25-foot birdie putt on the 17th that rolled in on its final turn, sending Woods into a series of fist pumps and more emotion that he had shown all week. With the match finally tied, he followed with a 3-iron from 218 yards on the par-5 18th that was so pure he twirled the club in his hand and walked toward the green, hands outstretched, until it stopped 8 feet away for eagle.
From a sure loss to an improbable win.
Instead of the Americans leading by a single point, they are up by three and in command of this Presidents Cup yet again.
"Don't overanalyze this whole thing," International captain Greg Norman said. "It was just great golf by Tiger Woods, making the putt on 17, turning the whole thing around, and he obviously hit a phenomenal shot on 18."
He had some help, of course.
Woods and Steve Stricker were perfect as Presidents Cup partners -- the first team to ever go 4-0 in this competition -- and they got enough help from everyone else to give the United States a 12½-9½ lead.
Phil Mickelson nearly joined them with undefeated records, using different partners. Mickelson and Sean O'Hair, his third partner this week, teamed for an easy foursomes victory in the morning and each had a birdie putt on the final hole in fourballs to win another match. Both missed and they settled for a halve.
Even so, even the half-points pushed the Americans closer to the 17½ points they need to win the cup.
"I think we all like our position," Jim Furyk said. "We still realize that you have to play well tomorrow, and you have to get the job done."
The International team walked away from Harding Park the last two days with momentum from keeping close. But as darkness fell across from Lake Merced, the deficit looked daunting with only 12 singles matches remaining Sunday.
No team has rallied from three points behind on the final day to win the cup outright, and the Americans have lost only one singles session in the seven previous Presidents Cup matches.
"Last time we had a five-point mountain to climb in Montreal, and it looks like we will have something to climb," Geoff Ogilvy said after collecting his first point of the week in teaming with fellow Australian Robert Allenby.
Hunter Mahan will lead it off for the Americans against Camilo Villegas, who has yet to win a point. Woods gets another crack at Y.E. Yang, who rallied to beat him in the PGA Championship, and 18-year-old Ryo Ishikawa will face 49-year-old Kenny Perry.
"I'm going to stick to my game plan, just like I did then," Yang said. "I'll have a few tricks up my sleeve, perhaps."
Woods has lost his last two Presidents Cup singles matches.
As a partner? He's never been better.
Their perfect mark was in jeopardy in the morning, when the International team was ahead in the final three matches on the course, needing wins in all of them to forge a tie.
Woods and Stricker, who had missed four putts inside 8 feet during a six-hole stretch in the middle of the match, were on the verge of being closed out on the 17th hole. The International team was 1 up, with Mike Weir facing 5 feet for birdie. Woods tried to drive the green and found the bunker, and Stricker hit a poor shot to 25 feet.
If Woods missed it, Weir could have won the match by making his short birdie putt.
In a shocking turnaround, Woods made his birdie and Weir missed his putt, and the match was all square, headed for the 18th.
"The stage is set, and he comes through again today," Stricker said. "It's pretty impressive."
Even better was Woods' 3-iron, which led to an eagle that was conceded when Weir hit into a bunker, and Tim Clark blasted 35 feet past the cup as the International team had to settle for par.
"It was fun to watch," Stricker said. "I had a front-row seat for that. That was pretty cool."
Those two matches -- a three-point swing -- gave the Americans a 10-7 lead after the morning.
In afternoon fourballs, Woods only had to watch Stricker make one long birdie putt after another in a 4-and-2 victory over Yang and Ishikawa, the first loss for the Asian duo.
"He was a stud all day," Woods said. "Stricks just put on a show. It was just an exhibition on how to putt."
Mickelson might have to settle for being the best player in red, white and blue this week. He brought O'Hair to life in their 5-and-3 victory in foursomes, then came up with the biggest shots in a late fourballs rally against Singh and Clark.
The International side was 2 up with seven holes to play until Mickelson birdied the 12th and O'Hair birdied the next hole. Clark stuffed it so close on the 14th that the birdie was conceded, and Mickelson then matched the birdie with a 40-foot putt.
The only thing Lefty didn't do was make the final putt.
No matter. The lead is still three points, and the Americans need to win only five of the 12 singles matches to hoist the gold cup. They have never lost the Presidents Cup on American soil, and they have an overall lead of 47½-36½ in singles.