Roger Federer

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Roger Federer

Power 100 rank: 17
Sport: ATP Tennis
Age: 28
Most recent notable achievement: Set record for Career Grand Slam Titles in 2009
Earnings: $32.8 million
Key sponsors: Nike, Rolex, Gillette, Mercedes-Benz

Why he's on the list: Though Federer entered 2009 slumping, he left it scorching. He won at Wimbledon to clinch the record for all-time Grand Slam titles and establish his place among the greats, all while heading a Gillette national TV campaign.