Paris, France (SportsNetwork.com) - Fourth-seeded Petra Kvitova and fifth seed Caroline Wozniacki notched opening-round wins, while struggling Canadian star Genie Bouchard was shown the door Tuesday at the 2015 French Open.

The Wimbledon champion and recent Madrid titlist Kvitova gutted out a 6-4, 3-6, 6-4 win over New Zealand's Marina Erakovic, while the U.S. Open runner-up Wozniacki waltzed past last week's Nurnberg clay-court champ Karin Knapp of Italy 6-3, 6-0.

And surging Frenchwoman Kristina Mladenovic erased the sixth-seeded Bouchard 6-4, 6-4. Mladenovic was a clay-court runner-up in Strasbourg, France, last week.

The 2014 Wimbledon runner-up Bouchard, who reached at least the quarterfinals in four of the previous five majors, has been playing poorly since appearing in the Australian Open quarters back in January.

Bouchard said she "had no expectations coming in."

A French Open semifinalist a year ago, Bouchard is now 7-10 overall this season, including five tournament-opening losses.

One of this year's Aussie Open semifinalists, 16th-seeded American Madison Keys, avoided an upset on Tuesday by topping fellow countrywoman Varvara Lepchenko 7-6 (7-3), 6-3.

Meanwhile, 10th-seeded German Andrea Petkovic whipped American Shelby Rogers 6-2, 6-1 and 18th-seeded Russian Svetlana Kuznetsova held off Dutchwoman Kiki Bertens 6-1, 4-6, 6-2. The two-time Grand Slam winner Kuznetsova was the French Open champion in 2009 and runner-up in 2006.

Bulgaria's Sesil Karatantcheva posted an upset by taking out 25th-seeded former world No. 1 Jelena Jankovic 6-3, 6-4. The former U.S. Open runner-up Jankovic is a three-time French Open semifinalist, but hasn't reached the final four here since 2010.

Also on Day 3, 23rd-seeded rising Swiss Timea Bacsinszky handled Spaniard Lara Arruabarrena 6-3, 6-4 and 32nd-seeded Zarina Diyas of Kazakhstan doused German Dinah Pfizenmaier 6-4, 6-1.

Several other women reached the second round, including former French Open champion Francesca Schiavone of Italy, American Irina Falconi and German Julia Goerges.