This steamy Spaniard is the No. 1 seed at this year's U.S. Open, and this is the only Grand Slam title missing from his resume. If Rafael Nadal, the King of Clay, can pull off a win this year, it will make the 24-year-old only the seventh man to win all four majors in his career. Nadal is shown here at the Rogers Cup on August 13, 2010 in Toronto, Canada. (Matthew Stockman/Getty Images)