The United States and Europe shared the opening foursomes 2-2 in the 39th Ryder Cup at Medinah Country Club on Friday.
The Americans took the first point through Phil Mickelson, winning a record ninth US cap, and rookie Keegan Bradley, who romped past the previously unbeaten Sergio Garcia and Luke Donald 4 and 3.
Then Ulstermen Rory McIlroy and Graeme McDowell won at the last against Brandt Snedeker and Jim Furyk.
The Irish duo had been three ahead after 11 holes but were pegged back to level by the Americans at the 16th.
A wild Snedeker drive at the last opened the door for Europe and McDowell sunk a four-footer for the win.
Rookie Jason Dufner produced a tremendous display of putting to ensure that he and Zach Johnson defeated Lee Westwood and Francesco Molinari 3 and 2.
But the session finished level when English pair Ian Poulter and Justin Rose defeated an out-of form Tiger Woods and Steve Stricker 2 and 1.
That match finished at the spectacular par-three 17th when Rose chipped Europe's second shot stone dead.
Huge crowds turned out at the suburban layout, the longest course ever used for the Ryder Cup, as the event came to Chicago for the first time.
The atmosphere was electric as McDowell got proceedings under way shortly after the crack of dawn, but it soon deflated as Europe took an early command, leaving US Davis Cup skipper complaining that it was all too quiet.
Europe were ahead in all four of the foursomes as the lead group stood on the eighth green, but it was Mickelson and Bradley that led the US fightback.
At one stage the advantage was briefly with the Americans, but a share of the spoils to get things going seemed a fair result for the morning's play.
It was the first time that had happened in the opening session of the Ryder Cup since 1997 at Valderrama in Spain.