Santoro, a 36-year-old who plans to retire at the end of this season, lost to Belgian Christophe Rochus 0-6, 6-4, 7-6 (7-3). Becker lost to Russian Evgeny Korolev 6-2, 6-3.
Eighth-seeded Croat Ivan Ljubicic, the 2005 champion, avoided an upset by rebounding to beat French qualifier Sebastien De Chaunac 4-6, 6-1, 7-6 (7-1).
Also Tuesday, Frenchman Richard Gasquet defeated German Michael Berrer 6-3, 2-6, 7-6 (7-5); Frenchman Thierry Ascione beat countryman Adrian Mannarino 7-6 (7-5), 6-4; and Frenchman Marc Gicquel beat Swiss Roman Valent 6-3, 6-1.
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