Paul Casey is to be dropped by his sponsors Titleist in the wake of his anti-American comments.
The Englishman told a Sunday newspaper he "hated" Americans but later stressed he was wrong to use the word and said it was taken in the wrong spirit.
But Acushnet - maker of Titleist clubs and balls - has taken a dim view.
"Mr Casey's contract expires on 31 December and both parties have mutually agreed that it will not be renewed or extended," said a statement.
Acushnet boss Wally Uihlein added: "We want people to understand that Mr Casey's comments do not reflect the views of the Acushnet Company and were not made in his capacity as an endorser of our products."
The decision seems likely to force Casey into a change of equipment if he signs a deal with another club manufacturer.
Casey, 27, sparked the row when he told a journalist that Europe were motivated for their famous Ryder Cup win over the USA in September because they "properly hated them".
He also said Americans have a "tendency to sort of wind people up" and
questioned the wisdom of Tom Lehman's appointment as next United States
But Casey, who lives in America and has an American coach and girlfriend, has since insisted: "I have nothing against the United States whatsoever and I wish I could take it back."