LOUISVILLE, Ky. — Phil Mickelson pointed his putter toward the cup, took a step and punched his fist to celebrate a clutch birdie. Boo Weekley revved up the crowd after holing a 50-foot putt from just off the green. Anthony Kim set a record for high-fives.

Yes, those were the Americans having all the fun yesterday at Valhalla.

At the Ryder Cup, no less.

"My cheeks are sore from smiling all day long," Justin Leonard said. "This was a lot different than my other Ryder Cup experiences."

In a stunning turnaround, the Americans rallied from a back-nine deficit four times to take a 5 1/2-2 1/2 lead, their largest margin after the opening day since continental Europe first was included in the Ryder Cup in 1979.

Mickelson and Kim twice came back from 3-hole deficits and picked up 1 1/2 points, as many as Lefty earned in the last two Ryder Cups combined. Leonard had never won a match in any Ryder Cup until two blowout victories with Hunter Mahan, one of six U.S. rookies who played like recent European dominance really was ancient history.

"We're in a good place," U.S. captain Paul Azinger said. "Who would have thought?"

The Americans hadn't led after any session since last winning the Ryder Cup in the "Miracle at Brookline" in 1999. But with six rookies and no Tiger Woods, they lost only one of eight matches and left European captain Nick Faldo wringing his hands.

Europe has won the past three Ryder Cups — and five of the past six — but now finds itself desperate to catch up.

"We've had a tough time," Faldo said. "We lost a few points, but we haven't lost any spirit."

One of the few bright spots for Europe was Lee Westwood, who tied Arnold Palmer by running his unbeaten streak in the Ryder Cup to 12 matches. Westwood and Soren Hansen birdied the last three holes in the final four-ball match of the afternoon, the last one enough to earn a halve against Weekley and big-hitting J.B. Holmes.

"It's a novelty, isn't it?" Westwood said. "It's not the position we wanted to be in, that's for sure."

Westwood landed in an even worse spot after the long day. In a surprising move, Faldo decided to bench Westwood and Sergio Garcia for this morning's foursomes. Neither has ever missed a Ryder Cup match — 27 straight for Westwood, 22 straight for Garcia. Combined, they have a 27-5-8 record in team play.

Rarely has a European captain shook up his lineup so drastically. But then, rarely is Europe behind.

Azinger sent out the same players for this morning foursomes that he used on opening day, which produced a 3-1 lead. It was the first time the U.S. team won the first session of the Ryder Cup since 1991.

"We've got a long, long way to go," Azinger said. "And we know how good they are."

In the opening match, Mickelson and Kim trailed by three holes with six to play until winning three straight holes and earning a halve against Padraig Harrington and Robert Karlsson. Down by three after four holes in the afternoon, Kim gave them their first lead of the day with a 7-foot birdie on the 14th, and Mickelson dropped in a 20-foot birdie on the 17th that led to a 2-up victory.

"We played with a lot of heart and a lot of emotion today to pull the halve and win out," Mickelson said. "We have a lot of work to do."

It was a big day for most of the U.S. rookies, who went 3-2-3.

Leonard teamed with one of those rookies, Hunter Mahan, and they won both matches without reaching the 17th hole. The afternoon victory came at the expense of Garcia, who finally looked ordinary in the Ryder Cup.

It was the first time Garcia failed to win a match in a single day.

Garcia had been undefeated in foursomes (8-0) but had to settle for a halve with Westwood in the morning. Kenny Perry, the lone disappointment for Kentucky, missed a 5-foot par putt that would have won the match on the 17th, then drove into the water on the 18th hole to allow Europe to catch them.

Leonard and Mahan then handed Garcia only his second loss in team matches by going 9 under through 15 holes, with Leonard finishing it off with a chip-in for birdie that had him pumping his fist.

Europe had the lead in all four morning matches in the first hour and only came away with one point.

In the afternoon, Europe had the lead in three matches going to the back nine, and came away with only 1 1/2 points.

Ian Poulter and Justin Rose won the only match for Europe, a 4-and-2 victory over Steve Stricker and Ben Curtis.