Floyd Mayweather Jr.

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Floyd Mayweather Jr.

Power 100 rank: 91
Sport: WBC welterweight boxer
Age: 32
Most recent notable achievement: Won 40th match (40-0) in 2009
Earnings: $30.3 million
Key sponsors: None

Why he's on the list: Pretty Boy Floyd came out of retirement in 2009 to build on his undefeated record and demonstrate that he is still one of the best pound-for-pound fighters in the world. He also would have been set to earn upwards of $25 million had he reached an agreement to fight fellow power boxer Manny Pacquiao.