I think that Roger Walkowiak deserves a mention.
Roger Walkowiak is 85 today.
He won the Tour de France in 1956, but his victory was so unexpected that it was met with very little enthusiasm and he spent many years actually being embarrassed by his win, even though it had been achieved at a record speed.
Walkowiak was unfairly treated by the French public and the phrase "à la Walko" came to mean "an unexpected win without any flamboyance".
He is however a legend who arose from being an unknown to win the worlds greatest cycle race.