American Ryan Harrison, an 18-year-old qualifier, upset No. 15 Ivan Ljubicic, 6-3, 6-7, 6-3, 6-4, in the first round of the 2010 U.S. Open Wednesday. The 6-foot-1 Harrison, who ESPN's Brad Gilbert compared to a young Andy Roddick, piled up 44 winners in his Open debut.
Check out Harrison's official bio, a recent feature about him in the Shreveport Times, and his Wikipedia page, which contains this nugget:
Harrison is notable for being the third youngest player since 1990, after Richard Gasquet and Rafael Nadal, to have won an ATP level match, defeating world #130 Pablo Cuevas in the 2008 U.S. Men's Clay Court Championships.