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Serena Williams
Power 100 rank: 18
Rank last year: 16
Sport: WTA Tennis
Age: 29
Most recent notable achievement: Won 2010 Australian Open and Wimbledon
Earnings: $20.2 million
Key sponsors: Nike, HP, Oreo, EA Sports, Gatorade
Rank last year: 16
Sport: WTA Tennis
Age: 29
Most recent notable achievement: Won 2010 Australian Open and Wimbledon
Earnings: $20.2 million
Key sponsors: Nike, HP, Oreo, EA Sports, Gatorade
Why she's on the list: Serena Williams dominated the decade in women's tennis, with 10 singles Grand Slam titles. She crushed the competition at Wimbledon this year without conceding a single set. She's also dominant off-court, where her endorsements are treasured. Williams has her own fashion line and appears regularly in cameo film and television roles.
