Defending Claro Open Colsanitas champion Teliana Pereira was stunned in the first round as the seeds otherwise enjoyed a good day.
Brazil's Pereira suffered a 3-6 6-3 7-6 (7-3) loss to Argentina's Catalina Pella at the WTA International event played on clay in Bogota.
The 23-year-old Pella has enjoyed an incredible year mostly on the ITF Tour and she carried that into Colombia, coming through qualifying before winning the first-round clash.
The seeds were otherwise untroubled as Irina Falconi, Tatjana Maria and Anna Tatishvili advanced.
Fifth seed Falconi crushed 15-year-old Emiliana Arango 6-0 6-1, Maria cruised past Marina Melnikova 6-1 6-3 and Anna Tatishvili overcame teenager Ipek Soylu 6-4 6-3.
Sweden's Rebecca Peterson enjoyed a 6-3 4-6 6-3 win over Daniela Seguel, while Silvia Soler-Espinosa beat Tereza Martincova 6-2 7-5.
Bulgarian Elitsa Kostova was too good for Laura Pous-Tio in a 6-4 6-3 win and Frenchwoman Sherazad Reix edged Sanaz Marand 6-3 7-6 (7-2).
Rain interrupted play at the tournament on Tuesday and two matches were unfinished.
Top seed Elina Svitolina trails Alexandra Panova 5-7 5-1, while two-time champion Lourdes Dominguez Lino and Patricia Maria Tig are locked at 5-5.