The top-seeded Ferrer bested Almagro, the defending Buenos Aires champ, 4-6, 6-3, 6-2, improving to 13-1 this year and 9-0 against Almagro for his career.
Ferrer bounced back after going down early, reeling off five aces to take the match in just under 2 hours on the red clay at Buenos Aires Lawn Tennis Club.
Ferrer lost to fellow Spaniard Juan Carlos Ferrero in the 2010 Buenos Aires finals.
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