Top seed Kiki Bertens was beaten at the Copa Colsanitas as former champion Lara Arruabarrena reached the semi-finals on Thursday.
Bertens had won through to the last eight earlier in the day with a 6-2 7-5 victory over fellow Dutchwoman and qualifier Cindy Burger.
But she went down in the quarter-finals, losing 6-1 6-4 to Italian veteran and wildcard Francesca Schiavone in Bogota.
Schiavone powered through in 75 minutes to reach a first semi-final since Rio de Janeiro early last year.
Awaiting the 36-year-old in the last four is Johanna Larsson, the Swedish third seed having overcome Sara Errani 7-5 6-4.
Arruabarrena, the 2012 champion of the WTA International event played on clay, battled into the last four.
The Spanish fourth seed edged past Serbia's Aleksandra Krunic 7-5 5-7 6-2 in two hours, 38 minutes.
An all-Spanish semi-final awaits after Sara Sorribes Tormo upset Polish fifth seed Magda Linette 6-4 4-6 7-6 (7-5).