The U.S. men's tennis team will limp into the second round, but Croatia's Goran Ivanisevic didn't even make it that far.
The No. 2 seed was upset by South Africa's Marcos Ondruska, 6-2, 6-4.
American Richey Reneberg, slated to play both singles and doubles, aggravated a groin injury and retired in the third set of his opening match against Leander Paes. Wimbledon finalist MaliVai Washington also won his Olympic debut, beating Slovakia's Jan Kroslak, 6-3, 7-6 (7-3).
American women, meanwhile, went 3-0 in first-round singles, with Mary Joe Fernandez and Lindsay Davenport joining Monica Seles in the round of 32. The seventh-seeded Fernandez beat Elena Likhovtseva, 6-2, 6-4, and No. 9 Davenport swept Anne Kremer, 6-2, 6-1.
Paul Haarhuis, the 12th seed, was the only other upset victim on the men's side, losing to unseeded Australian, Mark Philippoussis, 7-6 (7-4), 7-6, (7-2), who served 17 aces.
Thomas Enqvist of Sweden, faced down 24 aces from Marc-Kevin Goellner of Germany before winning, 7-6 (7-4), 4-6, 6-4.
On the women's side, seeded players Conchita Martinez of Spain, Anke Huber of Germany and Mary Pierce of France advanced easily.