Twelve months ago, the then-World No.174 Arruabarrena-Vecino announced herself to the tour with a surprise triumph at the International event 500 kilometers up the road in Bogotá. Now, settled inside the Top 100 and with a year's more experience under her belt, expectations for the Spaniard are somewhat higher.
In Dulgheru, though, Arruabarrena-Vecino faced a tricky second round opponent. Despite her lowly ranking of No.583, Dulgheru, who has been plagued by a long-term knee injury, is a two-time WTA titlist and was inside the Top 30 less than two years ago.
Since returning to tennis at the start of the year, after undergoing surgery on her troublesome knee last April, the Romanian has posted several encouraging results on the ITF Circuit and for the best part of two hours and three sets traded blows on equal terms with Arruabarrena-Vecino.
However, just as an upset appeared on the cards, Dulgheru flinched, throwing in three double faults to gift wrap the decisive break in the sixth game of the final set as she slipped to a 75 46 63 defeat.
Since reaching the quarterfinals of Roland Garros and breaking into the Top 50 as a precocious 15-year-old, Karatantcheva has enjoyed a rollercoaster career. Still just 23, Karatantcheva experienced an upturn in fortunes in 2012, briefly breaking back into the Top 100 and reestablishing herself as a fixture at Grand Slam level.
And she will have drawn further encouragement from her tenacious triumph over No.3 seed Cadantu; Karatantcheva recovered from the disappointment of frittering away a 5-2 second set lead - and spurning three match points - to eventually prevail, 64 57 62.
In the final match on Campo Central, Colombia's Castaño dug deep to fend off five set points in the opener before sending the crowd home happy with a 76(6) 62 win over No.2 seed Bratchikova.