Andujar moved on with a 6-4, 7-6 (7-5) victory over Colombian Santiago Giraldo, while Italian Simone Bolelli dispatched Spain's Robredo 6-2, 6-4.
Also posting a Day 1 victory was Argentine Martin Alund, who bested Brazilian wild card Ricardo Mello 6-4, 6-4.
Alund, a lucky loser, replaced fellow Argentine Leonardo Mayer in the main draw.
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