(CNN) -- World number one Rafael Nadal has been handed the top seeding for next month's U.S. Open at Flushing Meadows.
The tournament is the only one of the four grand slam events the Spaniard has yet to win, although he has reached the semifinals in the last two years.
Five-times champion Roger Federer is seeded second, with the Swiss aiming to become the first player to win six U.S. Open titles in the Open era.
Novak Djokovic -- the 2007 runner-up to Federer -- is seeded three while Andy Murray, the 2008 beaten finalist, completes the top four seeds for the New York event.
The are four American players in the top 20 seedings with Andy Roddick, John Isner, Mardy Fish and Sam Querrey flying the flag for the host nation.
Defending champion Juan Martin del Potro of Argentina and women's world number one Serena Williams have both been ruled out through injury.
Men's U.S. Open seeds:
1. Rafael Nadal (Sp)
2. Roger Federer (Swi)
3. Novak Djokovic (Ser)
4. Andy Murray (GB)
5. Robin Soderling (Swe)
6. Nikolay Davydenko (Rus)
7. Tomas Berdych (Cze)
8. Fernando Verdasco (Sp)
9 Andy Roddick (U.S.)
10.David Ferrer (Sp)
11.Marin Cilic (Cr)
12.Mikael Youzhny (Rus)
13 Jurgen Melzer (Aus)
14.Nicolas Almagro (Sp)
15.Ivan Ljubicic (Cro)
16.Marcos Baghdatis (Cyp)
17.Gael Monfils (Fr)
18.John Isner (U.S.)
19.Mardy Fish (U.S.)
20.Sam Querrey (U.S.)
21.Alberto Montanes (Sp)
22.Juan-Carlos Ferrero (Sp)
23.Feliciano Lopez (Sp)
24.Ernests Gulbis (Lat)
25.Stanislas Wawrinka (Swi)
26 Thomaz Bellucci (Brz)
27.Fernando Gonzalez (Chi)
28.Radek Stepanek (Cze)
29.Philipp Kohlschreiber (Ger)
30.Juan Monaco (Arg)
31.David Nalbandian (Arg)
32.Lleyton Hewitt (Aus)
