Holders Europe had their early grip loosened by the United States in the afternoon fourball matches after being outplayed in the morning foursomes at the Ryder Cup on Friday.

Trailing 1-3 after the opening session at Valhalla Golf Club, the Europeans initially led in three of the four encounters before the Americans pegged them back.

In pursuit of an unprecedented fourth consecutive victory in the biennial team competition, Europe were up in one match, down in one and all square in the other two.

British duo Ian Poulter and rookie Justin Rose, playing together for the second time on the day, were three up on 2003 British Open champion Ben Curtis and Steve Stricker with four holes to play.

Britain's Lee Westwood and Dane Soren Hansen surrendered an early two-up lead to lie all square with JB Holmes and Boo Weekley after 11 holes while Irishman Padraig Harrington and Britain's Graeme McDowell were level with Phil Mickelson and Anthony Kim after 16.

Americans Justin Leonard and Hunter Mahan, who won together in the morning, were on track for another point after going two up on Spaniards Sergio Garcia and Miguel Angel Jimenez after 12 holes.

Mahan, one of six rookies on the U.S. team, displayed superb form on Valhalla's contoured greens to give the 40,000 fans crammed around the par-71 layout good reason to cheer.

The Americans, bidding to end a run of five defeats in the last six matches, had mounted a gritty fightback in the morning to win the opening Cup session for the first time in 17 years.

Leonard and Mahan drew first blood with a 3&2 victory over Britain's Paul Casey and Swede Henrik Stenson after recovering from a bogey-bogey start.

Stewart Cink and Chad Campbell came from one down after 12 holes to edge Poulter and Rose one up before Mickelson and Kim halved a tight battle with three-times major winner Harrington and Swede Robert Karlsson.

In the final match of the morning, European heavyweights Garcia and Westwood fought back from two down with two to play to finish all square with local favourite Kenny Perry and Jim Furyk.

Garcia, an inspirational figure for Europe since his Cup debut in 1999, extended his unbeaten record in foursomes matches to 8-0-1 (win-loss-half).

"I was real proud of them for the way they hung in there, scratched and clawed and were able to finish," U.S captain Paul Azinger said after the Americans won an opening session for the first time since the 1991 matches at Kiawah Island.

"It's early, but I feel like we're in a pretty good place mentally right now and I just want to keep everybody on point.

"It's a nice start. I guess we haven't been ahead a long time in the morning, and can only be happy about it."

The United States are seeking their first triumph since their come-from-behind success at Brookline in 1999.