In the history of women's tennis, only Steffi Graf has won the Golden Slam, and in her case it was the even more elusive Golden Grand Slam a gold medal in the same calendar year that she also won the Grand Slam, a rare achievement that can only happen if a player is peaking during an Olympic year.

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He is a two-time US Open Champion and has won all four Grand Slam singles titles, and has victories in Davis Cup, Masters Series and an Olympic gold medal thanks to his precision and exceptional timing.

FORBES: Tennis Greats And Time: Agassi And Graf