Prague, Czech Republic (SportsNetwork.com) - Czech favorites Karolina Pliskova and Barbora Strycova were among Tuesday's first-round winners at the Prague Open.

The top-seeded Pliskova overcame German Annika Beck 2-6, 6-1, 6-3, while the third-seeded 2010 Prague runner-up Strycova topped American Madison Brengle 7-6 (7-5), 6-3.

A Day-2 upset came when Croatian qualifier Ana Konjuh ousted seventh-seeded Swiss fellow teenager Belinda Bencic 7-5, 6-7 (6-7), 7-6 (7-3).

Meanwhile, Czech wild card Klara Koukalova beat German Julia Goerges 7-6 (7-3), 6-2, Bulgarian Tsvetana Pironkova defeated Belarusian qualifier Olga Govortsova 7-5, 6-1 and qualifier Danka Kovinic of Montenegro dismissed Romanian Monica Niculescu 6-2, 2-6, 6-4 on the red clay.

Second-seeded Lucie Safarova was scheduled to meet fellow Czech Tereza Smitkova on Tuesday, but that opening-rounder was postponed because of rain.

In some second-round action on Wednesday, Pliskova will take on Pironkova and Strycova will battle Russian Elena Vesnina.