Mervyn Davies, a key member of Wales's triumphant 1970s side, died this morning at the age of 65 after losing his battle with cancer.
Davies, nicknamed 'Merv the Swerve' throughout the rugby world, was widely regarded as one of the standout players during the heyday of Welsh rugby.
The number eight, who was today described by the Welsh Rugby Union as "one of the greats of the modern game", also toured twice with the British and Irish Lions, travelling with the series-winning squads to New Zealand in 1971 and South Africa in 1974 and playing all four tests on both tours.
He captained his country in 1976 as his Welsh side secured another Grand Slam, and he was widely tipped to be made Lions captain in 1977.
But his playing career was cut short in 1976 when he suffered a brain haemorrhage during a club match and was forced to retire.
The WRU this morning announced Davies' death will be marked by a minute's silence before all Wales's Six Nations clashes tomorrow , including the senior side's showdown with France. Flags at the Millennium Stadium are already flying at half mast to honour him.
WRU president Dennis Gethin paid tribute to Davies, whom he called a called "a great player, a wonderful ambassador for the game and a true gentlemen".
He added: "I played against Mervyn many times and knew just how good he was but I also grew to appreciate him as a true friend".
Meanwhile David Pickering, chairman of the WRU, said Davies was the epitome of Welsh rugby. "He was a giant of the game both on and off the field for London Welsh, Swansea, Wales, the Barbarians and the British and Irish Lions," said Pickering.
"He bore his illness with courage and his memory will undoubtedly live on within our game for all time."
Davies began his career at London Welsh in 1968 and made his debut for Wales the following year in a 17-3 win over Scotland at Murrayfield, a game in which fullback JPR Williams also made his maiden appearance. He went on to play for Wales 38 times, with all those caps coming in consecutive matches.
He grew a moustache and also sported a wide headband, making him familiar component in the red of Wales and of the Lions. He scored two tries in a remarkable international career, which - including Lions tests - saw him on the losing side just nine times. With Davies on the field, his sides won a further 31 matches and drew six.
Davies' Wales racked up more than 100 points on their way to completing their Grand Slam in 1976, but the captain remained hard to please. He warned against complacency even after a 21-9 opening weekend win over England, Wales's biggest win over their biggest rivals at Twickenham.
Speaking of the game's two-try hero, Davies said: "Only in one respect was it the best - the phenomenal performance of JPR Williams."
Just three weeks after leading Wales to a 19-13 win over France and their second consecutive Five Nations Championship title in March 1976, his career was cut cruelly short by a brain haemorrhage. He collapsed during the WRU Challenge Cup semi-final when playing for Swansea - to whom he moved in 1972 - against Pontypool.
In 2001, he became just the seventh Welshman to be inducted into the IRB's International Rugby Hall of Fame. He joined fellow 1970s legends Gareth Edwards, Barry John, JPR Williams and Gerald Davies, along with his 1971 Lions coach Carwyn James.
His reputation went before him and he was widely acknowledged across the rugby world as one of the best number eights ever to have played the game.
The late Scottish commentator Bill McLaren, known as the Voice of Rugby, included Davies as one of four Welshman in his all-time top XV, while New Zealand's Colin Meads picked him alongside Irish centre Mike Gibson as the key threats during the 1971 Lions tour.
He was also voted Wales's greatest number eight and greatest captain in a 2002 poll of Welsh fans.
WRU Group Chief Executive, Roger Lewis, said Davies was a giant in all senses of the word.
Mr Lewis said: "His loss will be felt across the rugby world because of the huge impact he had as an icon of the game. He stood out in one of our great Welsh teams but remained a modest and gentle man off the field of play throughout his life.
"He truly earned his place in the Hall of Fame and it is right and fitting that this weekend his memory will be honoured by everyone involved in Welsh rugby.
"I want to send our condolences to all his family and friends because Mervyn Davies was a true great".