Top-seeded Lindsay Davenport, 2004 runner-up Elena Dementieva and two-time finalist Kim Clijsters were among Monday's first-round winners, while defending champion Anastasia Myskina suffered an upset loss at the French Open. Davenport's fellow American Venus Williams was also among the Day-1 victors. The fifth-seeded Myskina became the first-ever defending Roland Garros champion to lose in the opening round when Spaniard Maria Sanchez Lorenzo sent her packing in 6-4, 4-6, 6-0 fashion on Court Chatrier. Myskina, who is just the third defending champion at a Grand Slam event to suffer a first-round loss, has dropped her last four matches overall and is a dismal 1-5 in her last six matches in a disappointing 2005 campaign (8-10). The great Steffi Graf lost to Lori McNeil at Wimbledon 1994 one year after titling at the All England Club, and Jennifer Capriati fell against German Marlene Weingartner at the 2003 Australian Open after heading to Melbourne as the two-time defending champ. The 24-year-old Myskina bested Dementieva in last year's historic all-Russian finale here. The world No. 1 Davenport rebounded from a tough first set to dismiss Slovenian Katarina Srebotnik 3-6, 6-2, 6-2. The three-time major titlist Davenport has never advanced beyond the semifinals at Roland Garros. Davenport was January's Australian Open runner-up to Serena Williams and hasn't won a Slam since the 2000 Aussie Open. Up next for the 28-year-old Davenport will be Chinese Shuai Peng, who disposed of French crowd favorite Mailyne Andrieux 6-0, 6-1. The 11th-seeded Williams waltzed past Spaniard Marta Marrero 6-3, 6-2 on Court Lenglen to record her fifth straight match win. The former world No. 1 star is fresh off her clay-court title at the inaugural Istanbul Cup, where Marrero was one of her victims a week ago. The four-time Grand Slam champion Williams was the 2002 French Open runner-up to her younger sister Serena. Up next for Venus will be capable Colombian Fabiola Zuluaga. The fourth-seeded Dementieva handled Czech Barbora Strycova 6-3, 6-3 to post her seventh win here in eight matches. Dementieva gave way to Myskina in last year's final in Paris and succumbed to Svetlana Kuznetsova in last year's all- Russian U.S. Open title match. Dementieva will encounter Croat Sanda Mamic in the second round. A 14th-seeded Clijsters downed American Meilen Tu 6-1, 6-0. The former world No. 1 Clijsters was the runner-up here in 2001 and 2003. Clijsters will meet Slovakian Ludmila Cervanova in the round of 64. In other matches involving top-16 seeds, No. 8 Swiss Patty Schnyder stifled Korean Yoon Jeong Cho 6-3, 6-4, No. 9 Russian Vera Zvonareva zipped past Austrian Yvonne Meusburger 6-3, 6-1 and No. 16 Russian Elena Likhovtseva came back to beat Ukrainian Yuliana Fedak 2-6, 6-4, 6-4. Other seeded winners were No. 18 Italian Silvia Farina Elia, No. 19 Japanese Shinobu Asagoe, No. 20 Slovakian Daniela Hantuchova, No. 21 Frenchwoman Mary Pierce, No. 27 American Amy Frazier, No. 31 Croat Karolina Sprem and No. 32 Italian Flavia Pennetta. France's Virginie Razzano took out 25th-seeded Russian Dinara Safina 6-3, 6-3. Additional Day-1 winners were Cervanova, Mamic, Zuluaga, Argentines Mariana Diaz-Oliva and Clarisa Fernandez, Colombian Catalina Castano, Czech Eva Birnerova, Croat Jelena Kostanic, Poland's Marta Domachowska, German Sandra Kloesel, Japanese Akiko Morigami, Spaniard Arantxa Parra Santonja, Bulgarian Sesil Karatantcheva, France's Emilie Loit and Swiss Emmanuelle Gagliardi. Opening-round action will conclude with 32 more matches on Tuesday, including ones for second-seeded Wimbledon champion Maria Sharapova, third-seeded French favorite Amelie Mauresmo, the sixth-seeded U.S. Open titlist Kuznetsova and 10th-seeded 2003 French Open champ Justine Henin-Hardenne. Sharapova will meet Russian Evgenia Linetskaya, the former world No. 1 Mauresmo will battle Aussie Evie Dominikovic, Kuznetsova will oppose France's Mathilde Johansson and the former No. 1 Henin-Hardenne will put a 17-match winning streak on the line against 2000 Roland Garros runner-up Conchita Martinez. Henin-Hardenne is 20-1 this season, including wins in her last three tournaments.