Cliff later became a respected commentator, writer and head of outside broadcasts for the BBC and will be forever associated with his commentary on the 1973 Barbarians vs. All Blacks match and iconic description of Gareth Edwards's famous try.
Speaking of the sad news, Cardiff Blues CEO, Richard Holland, said: "Cliff was one of rugby's greats and true gentlemen, an outstanding player whose exploits are legendary. Off the field he also achieved so much as a much-loved commentator and writer.
"He was a wonderful ambassador for our great sport and Wales. Our thoughts are with his family and friends at this sad time."