Serena Williams has withdrawn from the Hopman Cup at the turn of the year but expects to be fit in time for the Australian Open later in January.
Williams has pulled out of the team event with a hamstring injury leaving James Blake to partner Meghann Shaughnessy for America.
The United States have won the event five times and will remain top seeds for the tournament, which takes place in Perth from January 3-9.
Marat Safin has confirmed he will represent second-seeded Russia with his sister Dinara while host nation Australia are seeded fourth and will see Lleyton Hewitt partner Casey Dellacqua.
1.United States (Meghann Shaughnessy/James Blake)
2.Russia (Dinara Safina/Marat Safin)
3.France (Alize Cornet/Gilles Simon)
4.Australia (Casey Dellacqua/Lleyton Hewitt)
5.Italy (Flavia Pennetta/Simone Bolelli)
6.Germany (Sabine Lisicki/Nicolas Kiefer)
7.Slovak Republic (Dominika Cibulkova/Dominik Hrbaty)
8.Taiwan (Su-Wei Hsieh/Lu Yen-Hsun)