Tiger Woods led the tributes to golfing legend Arnold Palmer, who has died aged 87.

Palmer, who won seven major championships during his career and was fondly nicknamed 'The King', died in Pittsburgh on Sunday afternoon.

Alastair Johnson, CEO of Arnold Palmer Enterprises, confirmed that Palmer died of complications from heart problems.

Johnson said Palmer was admitted to the hospital on Thursday for some cardiovascular work and weakened over the last few days.

One of golf's greatest players whose immense popularity drew a legion of fans known as 'Arnie's Army', Palmer brought the county club game to the masses just as television was coming of age.

'It's hard to imagine golf without you or anyone more important to the game than the King,' Woods tweeted on Sunday night.

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Golfing legend Arnold Palmer (above, in April) died at the age of 87 on Sunday

'Thanks Arnold for your friendship, counsel and a lot of laughs,' he added.

'Your philanthropy and humility are part of your legend.'

In 2004 interview when Palmer played in his last Masters, Woods said: 'If it wasn't for Arnold, golf wouldn't be as popular as it is now.

'He's the one who basically brought it to the forefront on TV. If it wasn't for him and his excitement, his flair, the way he played, golf probably would not have had that type of excitement.

'And that's why he's the king.'

The USGA also paid tribute to Palmer, writing on Twitter: 'We are deeply saddened by the death of Arnold Palmer, golf's greatest ambassador, at age 87.'

Palmer's biographer James Dodson was also among those who paid tribute to the golfing great.

'We loved him with a mythic American joy,' Dodson said, according to Golfweek.

'He represented everything that is great about golf. The friendship, the fellowship, the laughter, the impossibility of golf, the sudden rapture moment that brings you back, a moment that you never forget, that's Arnold Palmer in spades.'

A young Arnold Palmer takes a swing for the camera around 1955 at an unknown golf course

Arnold Palmer holds the Claret Jug with his wife Winnie at the 1961 British Open Golf Championship. He was married to Winnie for 45 years until her death in 1999

Former House Speaker John Boehner wrote on Twitter: 'Arnold Palmer was a model of integrity, passion, and commitment.

'A great American who struck his way into history and our hearts.'

Palmer ranked among the most important figures in golf history - and it went well beyond his seven majors and 62 PGA Tour wins.

His good looks, devilish grin and go-for-broke manner made the elite sport appealing to one and all.

Beyond golf, Palmer was a pioneer in sports marketing, paving the way for scores of other athletes to reap in millions from endorsements.

Tributes to the golfer flooded in on Twitter from sports personalities such as Tiger Woods and Jason Sobel and politicians such as Condoleezza Rice

In 2005, Palmer married Kathleen (pictured together, above), who was with him when he died

Some four decades after his last PGA Tour win, he still ranked among the highest-earners in golf.

On the golf course, Palmer was an icon not for how often he won, but the way he did it.

He would hitch up his pants, drop a cigarette and attack the flags.

With powerful hands wrapped around the golf club, Palmer would slash at the ball with all of his might, then twist that muscular neck and squint to see where it went.

'When he hits the ball, the earth shakes,' Gene Littler once said.

Palmer rallied from seven shots behind to win a U.S. Open. He blew a seven-shot lead on the back nine to lose a U.S. Open.

He was never dull.

'I'm pleased that I was able to do what I did from a golfing standpoint,' Palmer said in 2008, two years after he played in his last official tournament. 'I would like to think that I left them more than just that.'

He left behind a gallery known as 'Arnie's Army,' which began at Augusta National with a small group of soldiers from nearby Fort Hood, and grew to include a legion of fans from every corner of the globe.

Tiger Woods is pictured standing behind Arnold Palmer at a Rolex media event ahead of the British Open golf championship on the Old Course in St. Andrews, Scotland on July 15, 2015

Palmer stopped playing the Masters in 2004 and hit the ceremonial tee shot every year until 2016, when age began to take a toll and he struggled with his balance.

It was Palmer who gave golf the modern version of the Grand Slam — winning all four professional majors in one year.

He came up with the idea after winning the Masters and U.S. Open in 1960. Palmer was runner-up at the British Open, later calling it one of the biggest disappointments of his career.

But his appearance alone invigorated the British Open, which Americans had been ignoring for years.

Palmer never won the PGA Championship, one major short of capturing a career Grand Slam.

But the standard he set went beyond trophies.

Palmer is seen smiling with his trophy and medal after winning the British Open Golf Championship by a single stroke in 1961

PALMER'S RECORD Masters - 1958, 1960, 1962, 1964 US Open - 1960 The Open - 1961, 1962 US PGA Championship - Palmer's best finish was 2nd in 1964, 1968 and 1970. He won 62 times on the PGA Tour to sit 5th in the all-time list. Advertisement

It was the way he treated people, looking everyone in the eye with a smile and a wink. He signed every autograph, making sure it was legible. He made every fan feel like an old friend.

Palmer never like being referred to as 'The King,' but the name stuck.

'It was back in the early '60s. I was playing pretty good, winning a lot of tournaments, and someone gave a speech and referred to me as 'The King,'' Palmer said in a November 2011 interview with the AP.

'I don't bask in it. I don't relish it. I tried for a long time to stop that and,' he said, pausing to shrug, 'there was no point.'

Palmer played at least one PGA Tour event every season for 52 consecutive years, ending with the 2004 Masters.

He spearheaded the growth of the 50-and-older Champions Tour, winning 10 times and drawing some of the biggest crowds.

He was equally successful off with golf course design, a wine collection, and apparel that included his famous logo of an umbrella.

He bought the Bay Hill Club & Lodge upon making his winter home in Orlando, Florida, and in 2007 the PGA Tour changed the name of the tournament to the Arnold Palmer Invitational.

Palmer gets a hug from Miss Golf during the 1958 Masters Tournament at Augusta National Golf Club

Palmer (right) presents Jack Nicklaus with his green jacket after winning the 1963 Masters

He also has a popular drink named after him, a combination of iced tea and lemonade that is known as an 'Arnold Palmer.'

Palmer has said that he often drank a mixture of the drinks at home, but ordered one at a bar in 1960 during the U.S. Open at the Cherry Hills Country Club in Denver.

He said a woman overheard his order and requested 'that Palmer drink' - giving the cocktail its name.

Irish golfer Padraig Harrington recalled eating in an Italian restaurant in Miami when he heard a customer order one.

'Think about it,' Harrington said. 'You don't go up there and order a 'Tiger Woods' at the bar.

'You can go up there and order an 'Arnold Palmer' in this country and the barman — he was a young man — knew what the drink was. That's in a league of your own.'

Mass-produced versions of the drink have been sold under Palmer's name since the early 2000s.

But nothing defined Palmer like that 1960 U.S. Open at Cherry Hills.

Palmer (left) is pictured with his fellow former Masters champions Jack Nicklaus and Gary Player in 2014

Palmer attends a press conference during the ceremonial tee-off before first round play in the 2012 Masters Golf Tournament at the Augusta National Golf Club in Augusta, Georgia

He was seven shots behind going into the final round when he ran into Bob Drum, a Pittsburgh sports writer.

Palmer asked if he could still win by shooting 65, which would give him a four-day total of 280. Drum told him that 280 'won't do you a damn bit of good.'

Incensed, Palmer headed to the first tee and drove the green on the par-4 opening hole to make birdie.

He birdied the next three holes, shot 65 and outlasted Ben Hogan and 20-year-old amateur Jack Nicklaus.

Palmer went head-to-head with Nicklaus two years later in a U.S. Open, the start of one of golf's most famous rivalries. It was one-sided.

Nicklaus went on to win 18 majors and was regarded as golf's greatest champion. Palmer won two more majors after that loss, and his last PGA Tour win came in 1973 at the Bob Hope Classic.

Tom Callahan once described the difference between Nicklaus and Palmer this way: It's as though God said to Nicklaus, 'You will have skills like no other,' then whispered to Palmer, 'But they will love you more.'

Honorary starter Arnold Palmer (right) is congratulated by fellow golf greats Gary Player (left) and Jack Nicklaus (center) after hitting his drive during the ceremonial tee-off before first round play in the 2012 Masters Golf Tournament

WHAT'S IN A NAME? FOR 'ARNOLD PALMER,' IT'S ICED TEA AND LEMONADE Arnold Palmer is pictured holding a glass of the beverage named after him, which contains a mixture of lemonade and iced tea Raise a glass to celebrate the life of golf's 'King' - and make it an Arnold Palmer. 'I imagine that Arnold Palmer walks into a restaurant and they ask him what he's drinking, and he says, "What the hell do you think I'm drinking,"' comedian Will Arnett once cracked. Some sports greats have a trophy named in their honor. Others, a spiffy stadium or a playing surface. Palmer, who died Sunday at 87, had a much more refreshing choice, a mixture of lemonade and iced tea that was named for him. He created a stir on the course and with his drink that made him as much a cultural icon as much as his Grand Slam victories. Around the world, all you had to do was say his name and you could get the perfect mix of iced tea and lemonade. Palmer loved iced tea and suggested to his wife, Winnie, one day that she make a big pitcher of the drink. For fun, he suggested a dose of lemonade to mix things up. He drank it for lunch and loved it so much that the concoction would become a part of his daily routine. 'I thought, boy, this is great babe,' he said in an ESPN documentary. 'I'm going to take it when I play golf. I'm going to take a thermos of iced tea and lemonade.' Palmer would stick his name and likeness on a mass produced Arnold Palmer drink distributed by Arizona Beverage Company The secret to a perfect Arnold Palmer, go heavy on the iced tea with just a splash of lemonade. Palmer said he was overheard ordering the drink in a restaurant and a nearby patron said she wanted an Arnold Palmer. Legend has it, the name stuck and - even if he didn't invented the drink, he sure did popularize the beverage. The perfection was in its simplicity, ideal for a summer day, the end of a round of golf or lunch with the kids. Palmer would stick his name and likeness on a mass produced Arnold Palmer drink distributed by Arizona Beverage Company. He poked fun at the drink in pop culture and appeared in an ESPN SportsCenter commercial where he stood in line and poured himself iced tea from one dispenser and lemonade from another to mix the drink. Palmer's drink was parodied down to his last day. 'The Simpsons' poked fun in Sunday's episode by having Homer Simpson plot with one of his friends to fill water guns with iced tea and lemonade so he could 'Arnold Palmer Lenny when he walks in!' 'Arnold Palmer Lenny. You're going to Arnold Palmer Lenny,' Marge Simpson said. 'Arnold Palmer was a golfer and he made up this drink where it's not a full glass of lemonade or a full glass of iced tea,' Homer explained. Yes, even a dolt like Homer Simpson could make the drink. And the rest of us could enjoy one. Advertisement

'I think he brought a lot more to the game than his game,' Nicklaus said in 2009.

'What I mean by that is, there's no question about his record and his ability to play the game. He was very, very good at that. But he obviously brought a lot more. He brought the hitch of his pants, the flair that he brought to the game, the fans that he brought into the game.'

Palmer combined power with charm, reckless abandon with graceful elegance. Golf no longer was a country club game for old men who were out of shape. He was a man's man, and he brought that spirit to the sport.

It made him a beloved figure, and brought riches long after he stopped competing.

That started with a handshake agreement with IMG founder Mark McCormack to represent Palmer in contract negotiations.

Palmer's image was everywhere, from motor oil to ketchup to financial services companies.

Even as late as 2011, nearly 40 years after his last PGA Tour win, Palmer was No. 3 on Golf Digest's list of top earners at $36million a year. He trailed only Woods and Phil Mickelson.

And after he returned to golf a few months after being diagnosed with prostate cancer in 1997, which had been caught early, Palmer winked at fans as he waded through the gallery.

'I'm not interested in being a hero,' Palmer said, implying that too much was made about his return from cancer. 'I just want to play some golf.'

That, perhaps, is his true epitaph. He lived to play.