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Jennifer Capriati at Age 14 Shortly After Turning Pro

Simon Bruty / Getty Images
Jennifer Capriati of the USA turned pro in March of 1990, shortly before her 14th birthday. Here she is a couple of months later, hitting one of the ferocious groundstrokes for which she was famous. She had an impressive debut year, getting to the semifinals at Roland Garros and the fourth rounds of Wimbledon and the US Open. After a couple of troubled years off the tour in her later teens, she came back with a newfound happiness that helped her win two Australian Open singles titles and one at Roland Garros.