#1 Michael Chang

Michael Chang of USA caught the tennis world's attention as a junior level player who set several 'youngest ever' records. He remains the youngest ever player to win a US Open match at the age of 15. Standing at 5'9", Chang's serve was a big weakness of his against the taller players but he managed to offset his service speed with his quick reflexes, retrieving skills and defensive grind.
Chang won 34 Singles titles in his tennis career and was inducted into the International Tennis Hall of Fame in 2008, 5 years after his retirement from the sport in 2003. Chang won his first and only Grand Slam title at the 1989 French Open beating Stefan Edberg in a 5-set contest.
He was only 17 years, 3 months and 7 days old at the time making him the youngest Men's Grand Slam winner in the history of tennis. Chang is presently the coach of Japan's Kei Nishikori.
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