Pennetta, of Italy, defeated Spanish veteran Maria Sanchez Lorenzo, 6-1, 6-4, while Dominguez Lino posted a 6-1, 6-3, victory over Slovak Ludmila Cervanova.
Pennetta has won nine straight matches in this tournament, including a 7-6 (7-4), 6-4, decision over Dominguez Lino in last year's final.
Dominguez Lino, who is 8-1 in Bogota over the past two years, is seeking her first career championship in a WTA event. Pennetta has three career titles and reached the final at Gold Coast last month.
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