Mike Weir had chipped to 3 1/2 feet, certainly no gimme for his partner Vijay Singh.
The Canadian crowd that had cheered so wildly for Weir and the International team grew silent, enough for Mickelson to hear that familiar high-pitched tone of U.S. captain Jack Nicklaus.
"What do you want to do with (his) putt?'' Nicklaus asked.
Mickelson understood the question to be a directive, and he didn't hesitate to concede the putt and halve the match.
It was the most poignant moment Thursday at Royal Montreal, a day filled with gray skies and American red numbers on the scoreboard. The concession assured the International team a half-point, and it turned out to be the only thing it earned in the biggest opening-session rout in seven years at the Presidents Cup.
With clutch play from rookies Austin and Lucas Glover, and solid play from Mickelson and Tiger Woods, the Americans won 5 1/2 points in the six alternate-shot matches to seize early control of these matches.
"Our guys were sensational today,'' Nicklaus said. "They finished the matches. They played great. And I'm happy that Mike Weir from Canada got on the board.''
Nicklaus made sure of that, although Mickelson believes Singh would have made the putt.
It was typical coming from Nicklaus, who conceded a putt about the same length to Tony Jacklin in the 1969 Ryder Cup that allowed those matches to end in a draw. That gesture became a symbol of sportsmanship in matches between countries and continents.
"Captain Nicklaus was right. It was the right thing to do,'' Mickelson said after he and Austin rallied from 3 down over the final seven holes in a match in which only six holes were halved. "It was a hard-fought battle. There didn't need to be a winner or a loser.''
Then again, this was only Thursday. And it was clear the Americans were in charge.
It was the biggest blowout in the opening session since the United States won all five matches in 2000 on its way to the most lopsided victory in the short history of the Presidents Cup.
Steve Stricker and Hunter Mahan made a birdie on the first hole of the opening match and never trailed on their way to the easiest victory of the round, 3 and 2, over Adam Scott and Geoff Ogilvy. Woods and Charles Howell III were in the last match, the only other one that did not go the distance. Howell redeemed himself from an awful tee shot with a 15-foot par, and Woods closed out the 3-and-1 victory over K.J. Choi and Nick O'Hern with a tee shot to 3 feet on the 17th.
"We've seen this board the last two Ryder Cups,'' Woods said of the lopsided margin. "On the European side.''
The difference came from the matches in between.
All of them went to the 18th green with the International team poised to win two of them and halve the other two. Instead, the United States won three of those matches to seize control, and International captain Gary Player blamed it on poor decisions.
"We've seen a lot of majors in the last few years lost on the last hole by the incorrect decision,'' Player said.
The best decision came from Nicklaus.
Weir and Singh won five out of seven holes to built a 3-up lead, only to see the Americans run off three straight birdies. In position for a fourth straight birdie, Singh holed out from the bunker on the 15th for a 1-up lead, and Mickelson answered two holes later by pouring in a 15-foot birdie that set up the final hole.
Austin pulled his approach into a bunker. Singh leaked his right of the green. Mickelson blasted out to 12 feet, and Austin made his third big putt on the back nine, shoving his fist toward the hole and clasping fists with Lefty.
Then came the concession.
"It doesn't surprise me with Jack or Gary,'' Weir said. "They do the right thing, and they have for their whole career. I'd like to think that if it was role reversal there, we would have done the same thing.''
The other tight matches were a disaster for the International side.
Ernie Els and Angel Cabrera, after getting run over early by Jim Furyk and David Toms, won two straight holes and had all the momentum on their side when Els made a 15-foot par putt to stay 1 down on the 16th. It looked even better when Furyk hit his tee shot into the water, and the best the Americans could do on the 18th was a bogey.
From in front of a lip in the bunker, Els played a fade to the front of the green, and Cabrera lagged the long putt to 4 feet. Mickelson playfully told Nicklaus behind the green not to concede that putt, and it was a good thing. The Big Easy missed, giving the Americans a point.
Rory Sabbatini and Trevor Immelman were tied with Zach Johnson and Stewart Cink playing the 18th, and they made it easy on the Americans when Sabbatini hit his tee shot into the water. Johnson played a bunker shot to 2 feet for a conceded par, and another point.
Player said Sabbatini should have hit 3-wood off the tee, and said he spoke to him after the match.
"I don't like to interfere with my players at all,'' Player said. "He said, 'It was in my mind and I just made the wrong decision.' When you have four matches go to the last hole, that split decision is vitally important.''
Then there was Retief Goosen and Stuart Appleby, also tried to squeeze out a half-point with a win on the 18th hole. Appleby, however, pulled his approach so badly that it took 15 minutes to get a ruling, and Goosen's best option was to take a penalty stroke and hit their third shot over a row of corporate chalets. Lucas Glover and Scott Verplank made a par from the bunker for a 2-up victory.
Six better-ball matches are scheduled for Friday, and the International team can't afford to fall further behind.
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