Seve Ballesteros has been hailed as a "genius", "the king of European golf" and "Arnold Palmer and Jack Nicklaus rolled into one" following his death this morning.
The 54-year-old, who won five Majors and was instrumental in growing golf's popularity, passed away this morning due to respiratory failure.
The Spaniard had fought a long battle after being diagnosed with a brain tumour in 2008.
World number one Lee Westwood wrote on his Twitter feed: "It's a sad day, lost an inspiration, genius, role model, hero and friend. Seve made European golf what it is today. RIP Seve."
Bernard Gallacher, who captained Ballesteros in three Ryder Cups between 1991 and 1995, said: "Every European Tour player today should thank Seve for what they're playing for.
"America had Jack Nicklaus and Arnold Palmer - Seve was our Arnold Palmer and Jack Nicklaus rolled into one. You can't speak too highly of him, Seve was Europe's best ever player."
Ballesteros will forever be associated with the Ryder Cup, having helped Europe to lift the trophy in 1985, 1987, 1989 and 1995 before captaining them to another victory at Valderrama two years later.
And Gallacher said: "He felt it was his duty as the best player in the world to inspire the European team.
"When I became captain in 1991 he was still one of the best players in the world and he formed a formidable partnership with (Jose Maria) Olazabal, virtually unbeatable."
Ballesteros also delivered an inspirational message to Colin Montgomerie's victorious team at Celtic Manor last year, and Gallacher added: "Seve's best golf was played in the 1980s but he was still inspiring this new generation of golfers - the Martin Kaymers, the Ross Fishers, we've heard from Lee Westwood how as a young boy he would watch Seve and everyone would want to copy and emulate Seve.
Ballesteros' former Ryder Cup team-mate Howard Clark added: "When he came on the Ryder Cup scene he showed us exactly what could happen. In his last one in 1995 he led us into the singles and after six holes was level with Tom Lehman and playing dreadfully - he would say so himself."
Ballesteros would go on to lose, but not before taking the match to the 15th hole against all odds and Clark said: "It inspired the greatest recovery, I believe, from any Ryder Cup team on the last day."
On his career as a whole, Clark said: "We are looking at a top artist - the king of European golf, if you like, for many years.
"He brought excitement into the European game as Arnold Palmer did into the American game. Everybody drew another breath when he played - it was like watching a masterpiece."
European Tour chief executive George O'Grady said: "This is such a very sad day for all who love golf.
"Seve's unique legacy must be the inspiration he has given to so many to watch, support and play golf, and finally to fight a cruel illness with equal flair, passion, and fierce determination.
"We have all been so blessed to live in his era. He was the inspiration behind The European Tour."
Ballesteros' former caddie Billy Foster remembers him as "an absolute gentleman, the ultimate warrior".
Foster added on Sky Sports News: "There's not many players I've worked for in my time that have that aura about them. It was a special time - I was probably 25 years old, I'd caddied for maybe 10 years, and I got the ultimate dream chance of working for an absolute superstar."
Fears began to grow for Ballesteros after his family reported a serious deterioration in his condition last night, at which point his fellow Spaniard Sergio Garcia said: "He was a game-changer. To come from where he did and do what he did was amazing."
England's Paul Casey added: "He really blazed the trail for Europeans. Not only in the Ryder Cup, but also in how he played at Augusta and his victories over here. We owe a huge amount to him."
The flags at Real Club de Golf El Prat will be flown at half-mast in Ballesteros' for today's third round of the Spanish Open, while the players will wear black ribbons and there will also be a minute's silence.
Gonzaga Escauriaza, president of the RFEF (Spanish golf federation), told Marca: "He is the great icon of Spanish golf, one of the biggest characters in the sport in general, both inside and outside our borders, a genuine legend who changed the conception of our sport.
"Severiano Ballesteros has been an example of genius, determination and perseverance throughout his life.
"His loss gives us a great sadness, a hole which will not be possible to fill because Severiano Ballesteros has been a unique and never-to-be-repeated person.
"It is our duty to remember his achievements and pass them on to future generations his enormous greatness because he has left us an extraordinary legacy."
"Severiano Ballesteros always insisted on converting golf to a sport of the masses. We need to recognise that if now we are where we are, that if Spanish golf is a popular sport with a social base of more than 330,000 people, a large part of that is down to Severiano Ballesteros.
"Severiano did much for Spanish and European golf, with his innumerable triumphs, with his commitment to bringing the Ryder Cup to Spain in 1997 and with his insistence of combining tournaments in America and in Europe to relaunch the European Tour in a time when it was going through many difficulties. We all owe him a lot."