Ferrer bested Federico Delbonis in straight sets 7-6, 6-1, continuing his momentum after winning last week's Copa Claro in Buenos Aires.
Fellow Spaniard Robredo, meanwhile, had little trouble dismissing Serbia's Dusan Lajovic 6-2, 6-1 at Jockey Club Brasileiro.
Also Wednesday, No. 8 Pablo Andujar of Spain moved on in a walkover after Slovakia's Martin Klizan retired before the start of their match with an upset stomach.
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