The United States pitched a shutout in five alternate-shot matches in the crisp morning, then turned back an International rally with one of its own to split the afternoon fourballs and build a 14 1/2 -7 1/2 lead going into the 12 singles matches Sunday.
Mickelson and Austin combined to birdie their last two holes to steal a half-point, Tiger Woods recorded two blowouts with different partners, and Stewart Cink made all the clutch putts to turn a loss into another point that filled the scoreboard with American red numbers.
It now appears that for the second time in three weeks, the Sunday chase for a cup will be anticlimactic. Woods essentially wrapped up the FedEx Cup at East Lake before the weekend arrived, and only the greatest comeback in Presidents Cup history will keep this event from turning into a snoozer at Royal Montreal.
'It's not over,' International captain Gary Player said. 'But things don't look too good. The egg is not sunny-side up.'
Indeed, the International squad looked fried.
Mike Weir and Ernie Els had the only easy time in the afternoon for their team, and the deflating day ended with Vijay Singh curling in a 4-foot par putt that kept another International team from a collapse.
The only drama Sunday could come from Woods playing Weir in the fourth match, Canada's biggest golf star against a global icon.
'Mike Weir has nothing to lose,' Player said. 'It would be a phenomenal day in his career if he can beat Tiger.'
U.S. captain Jack Nicklaus nodded his head and clapped his hands with each point moving the Americans closer to their first outright victory on the road in the Presidents Cup, and their first in any cup since winning the Ryder Cup at The Belfry in 1993.
Mickelson provided the most entertaining moment when his ball caromed off the hill and into a shallow spot in the water left of the 15th green. Austin, his partner in the fourball match, walked over to look at the situation and shrugged his shoulders as if to say, 'Your turn to give it a try.' A day earlier, Austin lost his balance trying such a shot and wound up face-first in the water.
Mickelson borrowed the size-14 sneaker from his caddie to put on his left foot and go into the water. The ball tumbled back into the hazard, but at least Lefty didn't take the fall, even though they fell 1 down.
'I don't know if he thought he was going to lose the tag of Aquaman,' Mickelson said. 'I don't think that's going to do it.'
They went dormie on the next hole when Retief Goosen holed out from a deep bunker as he and Adam Scott went 2 up, but Austin made a 10-foot birdie on the 17th, and Mickelson halved the match with a 20-foot birdie on the final hole.
'We want to finish it off,' Mickelson said.
Player took Weir as a captain's pick, mostly because these matches came to Canada for the first time, and it was a good move. Weir ran off three straight birdies at the turn to give his team a commanding lead, and they closed out Charles Howell III and Lucas Glover, 4 and 2.
But now, those cheers are only a consolation prize.
'It's mixed emotions,' Weir said. 'I'm glad that I'm playing well, but disappointed that the score isn't closer.'
Weir had said winning a Presidents Cup in Canada might rival his 2003 victory in the Masters. But he isn't getting much help from the rest of the International team, which looks a lot like the United States in the Ryder Cup.
The other team is always making the key putt, as Jim Furyk did on the 13th hole in his fourball match. The momentum always seems to be on the Americans' side, even when they are trailing early in the matches.
Nicklaus is showing no mercy.
After the 5-0 blitz in the morning, Nicklaus was asked if he'd like to see the score closer.
'Uh-uh,' he said through pursed lips.
'Why would you ever say to one of your guys, 'I hope you lose so it's close,'' Nicklaus said. 'Would I like to see the matches played well? Absolutely. Would I like to see it close? Absolutely. But as captain, I put them out to win every match.'
That they did -- or close to it.
Coming off his worst loss in a team match, Woods and Furyk built a quick lead and poured it on in the closing holes for a 5-and-4 victory over Scott and Els. Woods played with David Toms -- his 14th partner in cup competitions -- in a fourball match and again never trailed, easily beating Geoff Ogilvy and Nick O'Hern.
Woods went 3-1 in the team matches, his best record in the Presidents Cup or Ryder Cup.
Mickelson had not won a full point in the cups in eight matches until he and Austin were essentially handed victory by Goosen and Stuart Appleby, who failed to make a birdie and were 6 over when the match ended on the 14th hole.
The tougher test came in the afternoon against Goosen and Scott, who had not led in any match all week. But the 27-year-old Australian squared the match with a birdie on the 12th, and took his first lead with a par on the 15th, with all eyes on Mickelson and the lake.
Even with the gallery chanting his name, Mickelson wanted no part of this.
'Woody, I know you want to see me play this shot,' Mickelson said after asking him to putt his 5-footer for par. Austin missed, and Lefty had no choice but to put on his rain pants, then ask caddie Jim Mackay for his left shoe.
'Size 14, extra wide,' Mackay said later. 'I think it will be about a 12 in the morning with shrinkage.'
Singh holed a nervy 4-footer at the end to salvage a point, joining Weir with the most points (2 1/2 ) going into the singles. Six Americans have at least that many points, led by Toms at 3 1/2 . Scott Verplank, who rested in the afternoon, is the only player undefeated this week.