BARCELONA, Spain - It didn't take long for the upset bug to strike the red clay of the Barcelona Ladies Open, as the No.1 seed and 15th-ranked player in the world, Alizé Cornet, went down on Day 1.

Stéphanie Cohen-Aloro, who reached the semis last year in her only previous appearance at this event, disposed of her fellow Frenchwoman, 60 63. The 26-year-old is seeking her first career Sony Ericsson WTA Tour title but has fifth-seeded Carla Suárez Navarro, coming off a runner-up showing in Marbella last week, looming in her quarter of the draw.

The two other seeds in action Monday were victorious, as second-seeded Flavia Pennetta defeated Petra Kvitova, 63 63, and seventh-seeded Sara Errani edged Mathilde Johansson, 26 75 63. Also, Lucie Safarova beat Tsvetana Pironkova, 61 36 60, Magdalena Rybarikova got past Klara Zakopalova, 61 76(7), and Roberta Vinci topped Pauline Parmentier, 64 76(7).

Earlier in the day, Anabel Medina Garrigues - Spain's No.1 player - was forced to withdraw from the tournament due to an abdominal strain.

"The doctor has advised me not to play, because I could do more damage to it," Medina Garrigues said. "It's a real shame because I really wanted to play here. After all, playing in your country in front of your fans is what all players want. I hope that Barcelona enjoys a good week of women's tennis."

Tuesday's schedule is highlighted by No.4 seed Kaia Kanepi versus lucky loser Masa Zec Peskiric, Suárez Navarro against wildcard entrant and fellow Spaniard Estrella Cabeza Candela, sixth-seeded Maria Kirilenko - last year's champion - versus Camille Pin and No.8 seed Sorana Cirstea - fresh off her semifinal showing in Marbella - against qualifier Anastasiya Yakimova.