Hunter Mahan, 26

This former Oklahoma State star fired three rounds of 62, two of which tied course records, in 2007. He won the Travelers Championship in Hartford, played on the U.S. Presidents Cup team, going 2-3-0, and saw his World Ranking rise from 202nd to 41st. A three-time AJGA All-American and winner of the 1999 U.S. Junior, Mahan was only 21 when he started his first full year on Tour in 2004, the second youngest player behind fellow rookie Kevin Na.