Europe's victory at Bethpage Black in New York on Sunday came after three days where the American audience heckled and mocked the European players.
European star Rory McIlroy, who had to endure insults and other things, called the audience's behavior "unacceptable".
He gets support from American golf legend Tom Watson. The former American Ryder Cup captain means on social media that the audience crossed the line.
"I want to apologize for the rude and nasty behavior of the American audience at Bethpage. As a former player, captain and as an American, I am ashamed of the behavior", writes the eight-time major winner.