Top-seeded Venus Williams double-bageled Spaniard Marta Marrero 6-0, 6-0 in a second-round match Tuesday at the inaugural Istanbul Cup -- a final clay-court tuneup for the French Open. Williams, who received an opening-round bye this week, will meet a Russian in the quarterfinals, either seventh-seeded Anna Chakvetadze or unseeded Tatiana Panova. The four-time Grand Slam champion and former world No. 1 Williams is seeking her first title since May of last year. A pair of seeds posted opening-round wins on Day 2, while one other suffered an upset. Third-seeded Israeli Anna Smashnova held off Colombian Catalina Castano 6-3, 2-6, 6-2, fifth-seeded German Anna-Lena Groenefeld handled Argentine Mariana Diaz-Oliva 6-3, 7-5, but sixth-seeded American Meghann Shaughnessy was knocked out by Bulgarian qualifier Tszvetana Pironkova 6-3, 7-5. The little-known Pironkova is ranked 220th in the world. Other first-round wins came for Israeli Shahar Peer, Russian Elena Vesnina, Swiss Emmanuelle Gagliardi and Croat Ivana Abramovic.