BEIJING, August 13, 2008 (AFP) - Results from day four of the Olympic tennis tournament here on Wednesday (x denotes seeding):

Jurgen Melzer (Austria) bt Lu Yen-Hsun (TPE) 6-2, 6-4

Novak Djokovic (Serbia x3) bt Mikhail Youzhny (Russia x13) 7-6 (7/3), 6-3

Rafael Nadal (Spain x2) bt Igor Andreev (Russia) 6-4, 6-2

Fernando Gonzalez (CHI) bt Olivier Rochus (BEL) 6-0, 6-3

Paul-Henri Mathieu (France) bt Nicolas Kiefer (German x15) 6-3, 7-5

Roger Federer (SUI x1) bt Tomas Berdych (Czech x17) 6-3, 7-6 (7/4)

James Blake (USA x8) bt Gilles Simon (France x10) 6-4, 6-2

Sybille Bammer (Austria) bt Lucie Safarova (Czech) 7-5, 6-4

Li Na (China) bt Kaia Kanepi (EST) 4-6, 6-2, 6-0

Vera Zvonareva (Russia x9) bt Francesca Schiavone (Italy) 7/6 (7/4), 6-4

Venus Williams (USA x7) bt Victoria Azarenka (BLR x12) 6-3, 6-2

Dinara Safina (Russia x6) bt Zheng Jie (China) 6-4, 6-3

Elena Dementieva (Russia x5) bt Caroline Wozniacki (DEN) 7-6 (7/3), 6-2

Serena Williams (USA x4) bt Alize Cornet (France x15) 3-6, 6-3, 6-4

Jelena Jankovic (Serbia x2) bt Dominika Cibulkova (Slovakia) 7-5, 6-1