Zakopalova through in Rio
Top seed Klara Zakopalova progressed to the second round of the Rio Open with a 6-4 6-4 win over Mariana Duque Marino.
The Czech player saw off her Colombian opponent in an hour and 19 minutes, but the straightforward scoreline belied the back-and-forth nature of the contest.
Both players struggled on serve, with Zakopalova dropping hers four times and Duque Marino being broken on six occasions.
Zakopalova's success sets up a second-round meeting with Spaniard Silvia Soler Espinosa.
Elsewhere in the first round, second seed Francesca Schiavone was sent crashing out after being beaten 6-4 6-4 by Lourdes Dominguez Lino.
Dominguez Lino battled her way through after edging two tight sets against the former French Open champion, who cause was not helped by five double faults.
Dominguez Lino will next face South Africa's Chanelle Scheepers, who fought back from a set down to defeat Timea Babos of Hungary 2-6 6-3 6-2.
Seventh seed Barbora Zahlavova Strycova was also eliminated as Dinah Pfizenmaier claimed a 2-6 6-4 6-3 win against her.