Federer has never retired from a professional tennis match
Nineteen-time Grand Slam champion Roger Federer, who turned 36 on Tuesday, has never retired from a professional tennis match in his 1,358-match long career. The Swiss tennis star was continuously ranked in the top ten from October 2002 to November 2016, having made his professional debut in 1998. Federer has an Olympic gold medal in men's doubles.