While the top-ten players were busy slugging it out in Beijing (except for Andy Roddick, of course), 19-year-old Juan Martin del Potro was busy state side racking up the wins.

Del Potro won his fourth straight tournament Sunday, beating Viktor Troicki 6-3, 6-3 to take the Legg Mason Tennis Classic championship. The No. 19 player in the world has won his last 19 matches since June 25.

“I feel confidence,” del Potro said. “Because when I go to the court, and the other players know I beat 19 players in a row and nobody can beat me, it is good for me.”

In addition to the $80k pay out from the Legg Mason win, del Potro ousted Andy Roddick in the Countrywide Classic, won the Austrian Open and took the Mercedes Cup along with a SLK 350 to increase his year-to-date prize money to $679, 890.

Not bad for not yet 20.

Del Potro could add one more title before the U.S. Open late this month. He said he will fly to New Haven, Conn., on Monday, then make a decision on whether he will play in the Pilot Pen Tennis event.

Either way, del Potro's white-hot winning streak makes him one to watch at the 2008 US Open.

Photo: (AP Photo/Daniel Maurer)