Jason Day has withdrawn from the Presidents Cup because of a back injury. International team captain Ernie Els replaced him with Byeong Hun An of South Korea two weeks before play begins.
Day, a former No. 1 who has battled back problems in his career, says he was practicing in California when the injury occurred.
Els previously had used one of his four captain’s picks on Day, who failed to win this year. An gives the International team two South Koreans for the Dec. 12-15 matches at Royal Melbourne.
Day was planning to join his Presidents Cup teammates at the Australia Open next week. He says his doctors advised him to shut out all practice and competition.
An gives the International team a record-tying seven rookies as it tries to beat the U.S. for the first time since 1998. The Americans are captained by Tiger Woods.