Federer dropped Hanescu 6-3, 6-7 (5-7), 6-1 to advance to the third round.
No, 4 Andy Murray easily beat Andreas Seppi 6-4, 6-4; sixth-seeded Robin Soderling dropped Evgeny Korolev 6-2, 6-4; and No. 9 Jo-Wilfried Tsonga eliminated Marinko Matosevic 6-1, 6-3.
Seventh-seeded Andy Roddick was scheduled to meet the unseeded Yen-Hsun Lu.
Several lower-seeded players were upset. Twelfth-seeded Gael Monfils fell to Simon Greul 1-6, 6-2, 6-3; unseeded James Blake beat No. 13 David Ferrer 6-1, 6-4; and Dudi Sela ousted 14th-seeded Radek Stepanek 6-4, 1-6, 6-2.
Tommy Robredo, seeded 18th, and Jurgen Melzer, No. 22, won their matches Sunday.
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