Ana Ivanovic began her bid for a third Generali Ladies title by defeating Yanina Wickmayer of Belgium 6-2, 6-4 on Tuesday. Sloane Stephens overcame a slow start to beat Magdalena Rybarikova of Slovakia 6-3, 6-1 in the first round.
The third-seeded Ivanovic, who won the event in 2008 and 2010, served five aces and broke five times against Wickmayer, the 2009 winner. She next plays Francesca Schiavone of Italy.
"The result looked easier than it really was," Ivanovic said. "She made me work hard, especially in the second set."
Stephens, seeded second, dropped her first two service games but the 12th-ranked American broke Rybarikova three times to take the opening set. Stephens, who lost her only previous match against Rybarikova, held serve throughout the second set. Stephens next plays Germany's Andrea Petkovic, who defeated Austria's Yvonne Meusburger 6-3, 7-5.
Earlier, Camila Giorgi of Italy upset last year's finalist Julia Goerges of Germany 6-2, 6-3. The 105th-ranked Giorgi won three qualifying matches to reach the main draw.
In the second round, Giorgi faces fifth-seeded Kirsten Flipkens of Belgium, who rallied to beat 17-year-old Donna Vekic of Croatia 2-6, 6-2, 6-2. Austrian wild card Patricia Mayr-Achleitner defeated sixth-seeded Sorana Cirstea of Romania 1-6, 6-3, 6-4.
Fourth-seeded Carla Suarez Navarro of Spain ousted Kristyna Pliskova of the Czech Republic 6-2, 6-3, and seventh-seeded Dominika Cibulkova of Slovakia downed Annika Beck of Germany 3-6, 6-2, 6-1. Cibulkova next plays Katarzyna Piter of Poland, who defeated Irina-Camelia Begu of Romania 6-2, 4-6, 6-3.