US Sam Querrey serves a during the first single match of the Davis Cup semi-final against Spanish tennis...

...tennis player Rafael Nadal returns the ball during a Davis Cup semi-final match against US Sam Querrey, at Las Ventas bullring in Madrid on September 19, 2008. AFP PHOTO/Pedro ARMESTRE (Photo credit...

US tennis players Sam Querrey (L) and An US tennis players Sam Querrey (L) and Andy Roddick joke during the draw...

...From L to R) US tennis coach Patrick McEnroe, players Mike Bryan, Mardy Fish, Andy Roddick, Sam Querrey, Spanish players Fernando Verdasco, Feliciano Lopez, David Ferrer, Rafael Nadal and coach Emilio Sanchez pose during...

NEW YORK - AUGUST 26: Sam Querrey of the United States celebrates after defeating Tomas Berdych of the Czech Republic during Day 2...

...one Rafael Nadal of Spain pumps his fist during his US Open fourth round match against Sam Querrey of the US on September 1, 2008 at the USTA National Tennis Center in New York...

Rafael Nadal of Spain returns against Sam Querrey of the USA at the US Open tennis tournament on September 1, 2008 at the USTA...

NEW YORK - SEPTEMBER 01: Rafael Nadal of Spain returns to Sam Querrey of the United States during Day 8 of the 2008 U.S. Open at the USTA...

Sam Querrey, of the United States, reacts to a missed shot during his match against Rafael Nadal, of...

Sam Querrey of the United States returns a shot to Tomas Berdych of the Czech Republic during their...

NEW YORK - AUGUST 30: Sam Querrey of the United States waves to the crowd after defeating Ivo Karlovic of Croatia during Day...

Sam Querrey

NEW YORK - AUGUST 26: Sam Querrey of the United States serves against Tomas Berdych of the Czech Republic during Day 2 of...

Sam Querrey of the United States returns a shot to Tomas Berdych of the Czech Republic during their...

Switzerland's Roger Federer returns the ball to United States player Sam Querrey during their first round match at the French Open tennis tournament in Paris on Monday May...