The United States trails Serbia 2-1 in a Davis Cup quarterfinal after the top-ranked doubles team of Bob and Mike Bryan lost to Serbia's Nenad Zimonjic and Ilija Bozoljac 7-6 (5), 7-6 (1), 5-7, 4-6, 15-13 on Saturday.
John Isner will play top-ranked Novak Djokovic in the first match Friday of the Davis Cup quarterfinal between the United States and Serbia.
Richard Gasquet of France has been replaced by Gilles Simon for singles on Friday against Argentina in the Davis Cup quarterfinals.
U.S. Davis Cup captain Jim Courier plans to face No. 1 Novak Djokovic and Serbia in the quarterfinals with the same group _ Sam Querrey, John Isner, twins Bob and Mike Bryan _ that beat Brazil in the first round.
The fourth singles in a Fed Cup series will be scrapped if a team has an unassailable 3-0 lead.
Serbia lost both reverse singles matches to Belgium on Sunday after it qualified for the Davis Cup quarterfinals a day earlier.
Querrey stepped up after teammate John Isner lost 2-6, 6-4, 6-7 (7), 6-4, 6-3 to Thomaz Bellucci earlier Sunday, forcing a deciding fifth match. It was the first time since 2000 that a U.S. team needed to win the fifth match to advance.
It was only the third time the Bryan brothers had dropped a Davis Cup match. It was just the second time that they had dropped a five-set match in ATP competition. Their only other five-set defeat was in a 1999 match at Wimbledon.
Australian Open champion Novak Djokovic of Serbia will face 127th-ranked Olivier Rochus of Belgium on Friday in the first round of the Davis Cup.
