Poulter and Rose take advantage of wayward Woods on the first morning at Medinah

Tiger Woods was hopelessly out of sorts as he and Steve Stricker crashed to a 2&1 foursomes defeat to Ian Poulter and Justin Rose in the opening session at Medinah.

Woods' snap-hook off the first tee set the tone for the round, during which he struck one spectator on the head and frequently left his partner in deep trouble.

Despite his horror first blow, Woods did manage a delicate chip to help match the Europeans' par, but Stricker then pulled his tee-shot to the short second into the water.

Poulter and Rose bogeyed the next, but Rose atoned by holing a slippery 35-foot putt for a winning birdie at the fourth.

The visitors won the sixth when Woods missed from six feet, but he pitched to three feet to set up a winning birdie at the seventh despite striking a spectator for the second day running.

The next three holes were halved, but Poulter then doubled Europe's lead when his bunker escape at the 11th dug in and curled into the cup.

Woods missed a seven-footer on the next, and Poulter hit back from a bogey at 13 with a crucial seven-foot putt for birdie at the 14th.

The Americans pulled one back with a fortunate birdie at 15 after Woods' drive ricocheted off a tree and finished close to the green.

But Poulter's nerve held again when he drained a 10-footer for a half at the 16th, and a solid par at the next was enough to seal his ninth Ryder Cup win in just 12 matches, and his first over Woods.