There's a new king in town.

22-year-old Rafael Nadal put an end to Roger Federer's 237-week run as No. 1 to claim the top spot in tennis.

It's been a three-year goal for the Spaniard, who has a child-like gaiety off the courts, and a focused intensity on the courts.  His all-out athletic style harkens back to the bull fighting days of Spain's yesteryear, transforming the tennis courts to a life-and-death arena where a battle waits to be won.

Coming off a Roland Garros win, a four-hour marathon victory over Federer at Wimbeldon and a freshly minted gold medal from the Olympics, Rafael Nadal is definitely the man of the hour in the 2008 US Open.

The hardcourts in New York, however, have not been kind to Nadal in his career – as he has never advanced past the quarterfinals and lost in the fourth round to buddy David Ferrer in 2008 after suffering from an injury to his left knee.

"I'm not so concerned about the way he hits ball, it's the way he moves and body type he has,'' said Paul Annacone, the men's head coach for Great Britain's Lawn Tennis Association. "He's a big, huge, strong athlete, but there's a lot of muscle mass to carry around. Like Boris Becker, he's big and he's doing all that stopping and starting, pounding side to side.

"The guys that reach that level the most efficiently and easily tend to have the longevity. That's Roger and Pete Sampras and Andre Agassi, to an extent. Rafa can play at really high levels. But it takes more out of him to do so. I'd say he is incrementally more vulnerable than someone like a Federer."

Nadal has proved this year he is a threat on all surfaces. Now he needs to prove he has the athletic and mental ability to remain at No. 1.

Photo: (Clive Brunskill/Getty)

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)