Tyson Gay | U.S.

A three-time gold medalist at the 2007 world championships, Gay has been the star of the show for the U.S. men's Olympic team, especially after setting an American record in the 100-meters at the trials in June with a time of 9.77 seconds. Though he injured his leg in the 200-meter trials, thereby eliminating his shot at competing in that event, he's expected to be fully recovered for the 100 by the opening ceremonies.