Kaymer was up against Steve Stricker. Level with two to go, the American bogeyed the short 17th after hitting his chip far too strongly.
Kaymer, bunkered off the final tee, found the green and had two putts for it once Stricker missed his long birdie attempt.
He gave himself and his team-mates palpitations when he sent his first one six feet past, but 21 years on from compatriot Bernhard Langer missing from the same distance to lose at Kiawah Island Kaymer made the one back and sparked jubilant scenes.
Moments before Molinari had fallen one down to Tiger Woods by bogeying the 17th himself, but suddenly it did not matter. The cup was going back across the Atlantic.
They played on, however, and when Woods bogeyed he conceded Molinari’s par putt – a move that gave Europe their fifth win in the last six games.
They won the 12 singles by a simply stunning 8 1/2-3 1/2 margin.
It was no surprise to see Olazabal, who of course formed with Ballesteros the greatest partnership in the event’s history, crying.
“It means a lot – not just for me,”’ he said. “This is for the whole of Europe, all those 12 wonderful men, my four vicecaptains and that band of caddies.
“Seve will always be present with this team. He was a big factor for this event and last night when we had that meeting I think the boys understood that believing was the big thing.
“It’s been a tough week.
Until today nothing went our way – we struggled on the greens, but this morning I felt we were a little better in that regard.
“I’ve been under pressure hitting shots, but today tops that.’’ Kaymer said: “It’s a feeling I’ve never had before.
Bernhard helped me so much, just to sit me down and talk about it.
‘‘Now I know how it feels to win the Ryder Cup.’’ Stunned American captain Davis Love said: ‘‘I would not have done anything differently. They played great.
‘‘When you lose a segment (session) that badly it’s going to cost you.’’ The only previous side to win from four down entering the singles was Ben Crenshaw’s in Boston in 1999 – a match that ended so controversially with a premature invasion of the 17th green.
Olazabal was on the receiving end of that, standing there as he waited for calm to be restored and then missing the putt which meant the Americans could not lose.
That was just another dimension to how sweet this day must have felt.
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