The U.S. team of Roddick, 12-ranked James Blake and world No. 1 doubles team of twin brothers Bob and Mike Bryan -- the same group that won the Davis Cup last year -- opens its 2008 Davis Cup season with a best-of-five series in Vienna.
The Austrians, who have chosen an indoor red clay surface for the matches, counter with Melzer, ranked 57th in the world; Stefan Koubek, ranked 55th; and the doubles team of Melzer and Julian Knowle.
After Melzer and Roddick open singles play Friday, Blake is to go against Koubek. The doubles match is scheduled for Saturday with reverse singles wrapping up the series on Sunday.
This weekend marks the third time the United States has played Austria in Davis Cup competition, with the Americans winning both previous meetings. The U.S. team won 3-2 on clay in Vienna in 1990 and 5-0 in Connecticut in 2004.
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