Paris, France (SportsNetwork.com) - Last year's runner-up Sara Errani was an easy second-round winner, while former champion Petra Kvitova pulled out of the draw Thursday at the GDF Suez Open in Paris.
The second-seeded Kvitova was scheduled to play France's Alize Cornet on Day 4, but decided to exit the draw due to a respiratory illness.
"I was absolutely intent on playing today but I had to see my doctor as I wasn't feeling well," said the 2011 champion Kvitova.
"I've got a sore throat and after practicing this morning I realized that after 10 minutes I wasn't able to breathe so unfortunately I was forced to withdraw."
Kvitova was replaced in the draw by lucky loser Barbora Zahlavova Strycova of the Czech Republic.
The third-seeded Errani cruised past fellow Italian Karin Knapp 6-4, 6-3 and will face Ukrainian Elina Svitolina in Friday's quarterfinals. Svitolina subdued Kazakhstani qualifier Galina Voskoboeva 6-1, 6-2.
Errani lost to German Mona Barthel in last year's finale in Paris.
Also on Thursday, eighth-seeded Belgian Kirsten Flipkens drilled Austrian Yvonne Meusburger 6-1, 6-3 and German Andrea Petkovic pasted French wild card Kristina Mladenovic 6-4, 6-2. Flipkens is rewarded with a quarterfinal against top-seeded Maria Sharapova.
This week's champion will claim $132,000.