Hingis, the defending champion, clubbed Frenchwoman Nathalie Dechy, 6-1, 6-1, and Sanchez-Vicario demolished American Kristina Brandi, 6-0, 6-2.

Fourth-seeded Mary Pierce of France beat Czech Kveta Hrdlickova, 6-3, 6-4; No. 5 Patty Schnyder of Switzerland eliminated Italian wild card Adriana Serra-Zanetti, 6-2, 7-5; seventh-seeded Nathalie Tauziat shut down Italian wild card Tathiana Garbin, 6-4, 6-2; and No. 8 Sandrine Testud dominated the all-French derby with Anne-Gaelle Sidot, 6-1, 6-1.

The top eight seeds received byes in the first round.

Ninth-seeded Russian Anna Kournikova is playing Spain's Magui Serna and No. 10 Amelie Mauresmo of France is meeting Russian qualifier Elena Dementieva later Wednesday.

Eleventh-seeded Dominique Van Roost survived a Belgian shootout with Sabine Appelmans, 6-4, 6-7 (2-7), 6-3; Austrian Sylvia Plischke pulled off the lone upset of the day, a 6-4, 2-6, 6-1 triumph over 12th seed Amanda Coetzer of South Africa; No. 13 Irina Spirlea of Romania smashed Greek qualifier Christina Papadaki, 6-4, 6-0; and 15th seed and four-time champion Conchita Martinez of Spain cruised past France's Sarah Pitkowski, 6-3, 6-3.

American Corina Morariu ousted Romanian Ruxandra Dragomir, 6-2, 6-3, and Tara Snyder of the United States takes on Anna Smashnova of Israel later Wednesday in matches involving unseeded players. Morariu won her first career title last week in Bol, Croatia.

Hingis returned to action after a one-month hiatus in preparation for the upcoming French Open. The 18-year-old improved to 27-4 this season with her victory Wednesday. She has won three singles titles in 1999, including her third straight Australian Open.

She was successful in her claycourt season debut last month, defeating doubles partner and fellow teenager Kournikova to capture the Family Circle Cup in Hilton Head, South Carolina.

After being sidelined for three months with a wrist injury, Sanchez-Vicario won her first title of the year at the Egypt Classic two weeks ago. She is coming off a semifinal loss to Venus Williams last week in Hamburg, Germany and will defend her French Open title in three weeks.

Fresh off winning her first career claycourt title in Hamburg, the third-seeded Williams held off Spain's Gala Leon Garcia, 7-5, 4-6, 6-4 Tuesday. Serena Williams, the sixth seed, had an easier time with Russia's Tatiana Panova, 6-2, 6-1, in her season debut on the dirt Tuesday.

First prize is $150,000.