WASHINGTON -- Sixteen-year-old Francis Tiafoe lost his ATP tour debut while fellow Americans Robby Ginepri and Donald Young won their opening round matches at the Citi Open on Monday.
Russia's Evgeny Donskoy defeated Tiafoe, the world's seventh-ranked junior player and a D.C.-area native, 6-4, 6-4.
Top-seeded Tomas Berdych will face Ginepri, who advanced to the second round with a 6-4, 6-2 victory over Alejandro Falla of Colombia 6-4, 6-2. Young beat Yuichi Sugita of Japan 6-4, 4-6, 6-4.
No. 6 seed Svetlana Kuznetsova of Russia won the opening match in the WTA draw, 6-3, 6-2 over Slovenia's Polona Hercog. 18-year-old American qualifier Taylor Townsend rallied for a 3-6, 6-2, 6-3 victory over Julia Goerges of Germany.
Tiafoe trains at the tennis center in the Maryland suburbs where his father once worked as a maintenance man and the family occasionally lived. This year the 6-foot-1 slugger played boys' singles at the French Open, where he was the top seed, and at Wimbledon.
Donskoy, ranked 111 on the ATP tour, fended off enough forehand winners from Tiafoe and possible momentum-altering roars from the partisan crowd to break the local favorite twice in the final set.
John Isner received a first-round bye, as did Wimbledon semifinalist Milos Raonic of Canada. Isner, a finalist in Washington last year, won the Atlanta title on Sunday.
Other ATP winners on Monday included Americans Tim Smyczek and Rajeev Ram, Australia's Bernard Tomic, France's Benoit Paire and Tunisia's Malek Jaziri.
American Vania King will join Kuznetsova and Townsend in the second round after cruising to a 6-2, 6-0 win against Canada's Francoise Abanda.