Aug. 9, 2009 (United Press International) -- Argentina's Juan Martin del Potro defended his title at the Legg Mason (NYSE:LM) Tennis Classic in Washington Sunday by downing American Andy Roddick in three sets.

After losing the first set 3-6, the second-seeded Del Potro came back with 7-5, 7-6 (8-6) wins to capture his second title of the year -- and become the first back-to-back winner at the Washington tournament since Andre Agassi won in 1998 and 1999.

Roddick, who has won the tournament three times, including 2007, said he felt good about his overall performance despite the loss Sunday.

"This is the start of preparation leading up to the U.S. Open," he said. "I feel better about my game now than when I got here."