Chaska - Command of the Ryder Cup hung on a knife's edge Saturday with Rory McIlroy leading a emotional European charge in morning alternate shot foursomes matches.
The United States led 5-3 after Friday's foursomes and four-ball sessions but Europe lead two matches and the Americans one early on Saturday with the fourth all square.
Third-ranked McIlroy, fist pumping and yelling with delight at big shots, and Belgian Thomas Pieters clung to a 1-up lead over Phil Mickelson and Rickie Fowler with six holes to play after jumping 3-up through the first four holes.
Olympic champion Justin Rose and English compatriot Chris Wood were 2-up through 10 holes over PGA Championship winner Jimmy Walker and two-time major champion Zach Johnson.
Jordan Spieth and Patrick Reed owned the only US lead, a decisive 3-up edge through nine holes over Spaniards Sergio Garcia and Rafa Cabrera Bello.
For Europe to level the overall score entering the afternoon four-ball matches, it would have to complete a turnaround of an all square match between Sweden's Henrik Stenson, the British Open champion, and 22-year-old Englishman Matthew Fitzpatrick and Americans Brooks Koepka and Brandt Snedeker.
The US duo led every hole until the Europeans birdied the 11th to pull level.
Play concludes at Hazeltine with 12 singles matches on Sunday.
Europe need 14 points to retain the Cup while the US team needs 14 1/2 to take the trophy.