Rome, Italy (SportsNetwork.com) - German Angelique Kerber and American Madison Keys were among Monday's seeded winners, as the women's $2.7 million Italian Open commenced in Rome.

The ninth-seeded left-handed Kerber clipped France's Alize Cornet, the 2008 Rome runner-up, 6-2, 6-3, while the 15th-seeded Australian Open semifinalist Keys took care of fellow American Madison Brengle 6-2, 6-4 on the red clay at Foro Italico.

The in-form Kerber was a recent clay-court titlist in both Stuttgart and Charleston.

A Day-1 upset came when Swiss two-time 2015 WTA event titlist Timea Bacsinszky knocked out 11th-seeded Czech and recent Prague champ Karolina Pliskova 6-4, 6-0.

Italian favorite and former French Open finalist Sara Errani reached the second round by holding off Slovakian veteran Daniela Hantuchova 6-4, 7-6 (7-4). The 13th-seeded Errani was last year's Rome runner-up to the great Serena Williams.

In other action involving Americans, Alison Riske leveled compatriot Varvara Lepchenko 6-4, 6-3 and Christina McHale bested Czech Barbora Strycova 7-6 (7-5), 6-1. Riske's second-round opponent will be second-seeded 2014 French Open runner-up Simona Halep.

Meanwhile, former Wimbledon runner-up Sabine Lisicki of Germany whipped Latvian Liga Dekmeijere 6-4, 6-1; Russian Anastasia Pavlyuchenkova dismissed former U.S. Open champion and 2011 Rome runner-up Samantha Stosur 6-4, 7-5; Brit Heather Watson bounced Italian Roberta Vinci 6-3, 6-1; and an all-Italian affair saw Karin Knapp erase former Roland Garros titlist Francesca Schiavone 6-4, 6-1.

Pavlyuchenkova is rewarded with a second-round match against the aforementioned world No. 1 superstar Williams, while Knapp will encounter last week's Madrid Open and reigning Wimbledon champion Petra Kvitova.

Williams is the two-time reigning and three-time overall Italian Open champ.

Additional wins came for Aussie Jarmila Gajdosova, Kazakhstan's Zarina Diyas and Slovak Magdalena Rybarikova. Gajdosova should have her hands full with third-seeded reigning French Open champ and two-time Italian Open winner Maria Sharapova in her next outing.