Panova knocked off Timea Babos of Hungary 6-2, 6-3, and Arrubarrena-Vecino defeated Edina Gallovits-Hall of Romania 6-4, 6-3 in Bogota.
Arrubarrena-Vecino saved 88 percent of her break points to 43 percent for Gallovits-Hall.
Sunday's finals will be the first WTA championship match for both players.
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