Palmer died at the UPMC Presbyterian Hospital in Pittsburgh, where he had been undergoing heart tests since Thursday, the Pittsburgh Post-Gazette reported.

“We are deeply saddened by the death of Arnold Palmer, golf’s greatest ambassador, at age 87,” the USGA said in a statement.

“Arnold Palmer will always be a champion, in every sense of the word.

“He inspired generations to love golf by sharing his competitive spirit, displaying sportsmanship, caring for golfers and golf fans, and serving as a lifelong ambassador for the sport.

“Our stories of him not only fill the pages of golf’s history books and the walls of the museum, but also our own personal golf memories. The game is indeed better because of him, and in so many ways, will never be the same.”

Nicknamed “The King,” Palmer won seven major championships during his playing career, which began in the 1950s, and was one of 13 original inductees to the World Golf Hall of Fame in 1974.

Palmer attracted a devoted legion of fans called “Arnie’s Army” through his magnificent performances on the golf links and magnetic personality.

Thanks Arnold for your friendship, counsel and a lot of laughs. Your philanthropy and humility are part of your legend.

— Tiger Woods (@TigerWoods) September 26, 2016

(2/2) It’s hard to imagine golf without you or anyone more important to the game than the King.

— Tiger Woods (@TigerWoods) September 26, 2016

He never won golf’s fourth major, the PGA Championships, where he finished runner-up on three occasions.

Along with other golfing greats Jack Nicklaus and Gary Player, Palmer is widely credited with popularising the sport around the world in the 1960s.

Palmer said goodbye to the US Open – which he won in 1960 at Oakmont – in 1994, and from the British Open – where he was a two-time winner – at St Andrews in 1995.

In 2002, Palmer played his 147th and final round on the illustrious links of the Augusta National, where he claimed four Masters championships.

“I just think it’s time. My golf has been pretty lousy of late, and it doesn’t warrant being here playing,” the then 72-year-old Palmer told reporters after shooting a 17-over 89 in the first round – matching his worst score ever in 48 appearances.

“I’m not any different than most people,” Palmer, the Masters winner in 1958, 1960, 1962 and 1964, said at the time.

“I like to think there’s always a couple more good rounds in my body, and maybe there are. But I haven’t shown up here.”

Palmer concentrating on his next move during the Lucky International Open at San Francisco’s Harding Park in 1962. Photo: AP

Palmer remained highly involved in golf after retiring, presiding over the annual Arnold Palmer Invitational, the only living player with his name attached to a PGA Tour event.

He received the two highest civilian honours in the United States – the Congressional Gold Medal in 2012 and the Presidential Medal of Freedom in 2004.

Palmer was also seen as an excellent businessman, a prominent advertising spokesman, a skilled aviator and a talented golf course designer.

His health had been in decline since late 2015, Golfweek reported, and a ceremonial tee shot at that year’s British Open was his last public golf shot.

-DPA