SAN FRANCISCO - For the briefest moment, it looked as though Justin Leonard only had to pick up his coin for the Americans to win the final match Thursday and take another big lead on opening day at the Presidents Cup.

First, there was some confusion over whether to concede his 3-foot putt.

Then came a shocking miss from Leonard.

The United States still wound up with a 3½-2½ lead at Harding Park, even if the International team claimed a partial victory.

“At the end, we were pretty fortunate to have 2½ points,” Ernie Els said. “That’s one of the better starts we’ve had, believe it or not, for the last three Cups or so. So we are not too despondent about today.”

After Tiger Woods and Steve Stricker dominated early, and Phil Mickelson and Anthony Kim came to life late in their foursomes match, a bizarre finish in the final match made it unclear who actually had the momentum going into Friday.

“We wanted to get out of the day with pretty close to a push, and I’m very, very happy,” International captain Greg Norman said.

Leonard and Jim Furyk had a 1-up lead playing the par-5 18th hole, and Leonard hit a splendid fairway metal to the green that left the Americans on the verge of another full point, especially after Furyk lagged the eagle putt to 3 feet. Retief Goosen hit his approach right of the green, Y.E. Yang chipped to 4 feet and Goosen made the birdie putt.

Then, the Goose forgot the score.

He removed his cap and looked at Furyk as if to ask why Leonard should putt, believing the match was all square. Once he realized what was at stake, Leonard settled over the putt and was stunned when it caught the right lip.

Leonard made no excuses.

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“I just hit a bad putt,” he said. “I knew I was going to need to make that little putt. Unfortunately, I missed it.”

U.S. captain Fred Couples said Goosen later spoke to him and Leonard and apologized for any misunderstanding.

“He didn’t mean anything by it, and Justin didn’t have a problem,” Couples said. “No one has a problem with it. Did we think we were going to be up 4-2? Yes, we really did. But it won’t be the last putt every missed at the Presidents Cup, and it won’t be the last time a reversal was done. So we’ll just come out tomorrow and try to get 3½ more points against this team.”

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It looked simple enough on a cool, cloudy day on this public course south of San Francisco.

Woods and Stricker played bogey-free in the difficult alternate-shot format, teaming up for six birdies in a 6-and-4 victory over Geoff Ogilvy and 18-year-old Ryo Ishikawa.

Mickelson and Kim, who sputtered around for 12 holes, closed with four straight birdies for a 3-and-2 victory over Tim Clark and Mike Weir, the only partnership that failed to produce a birdie at Harding Park.

The momentum switched to American red on the scoreboard late, and the final push figured to come from Leonard and Furyk, who made a furious rally in the middle of the match by winning four straight holes to take the lead. They were 2 up with two to play.

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Goosen holed a birdie putt on the 17th to send the match to the par-5 18th, setting up the odd conclusion.

“I was a little confused by the whole thing, to tell you the truth,” Stricker said. “It looked like he was going to give him the putt. Obviously, he didn’t. We talked to Jim Furyk, and nothing was ever conceded. But from everybody standing there on the side, it kind of looked like he was going to give it to him.”

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Norman said there was no gamesmanship on Goosen’s part.

“He thought the match was over,” Norman said. “He didn’t concede the putt. He just thought the match was over. It was a legitimate mistake, and no intent or malice. It was just the intensity of the game.”