PARIS, May 25 (UPI) -- Serena Williams opens defense of her French Open crown Monday as she attempts to continue her domination of Grand Slam events.
Williams will be a part of the opening-day action when she takes on Germany's Barbara Rittner.
Last year at Roland Garros, Williams claimed her first Grand Slam since the 1999 U.S. Open, starting a string of four straight major titles. She beat her older sister, Venus, in the first French Open final for both women but the second of what became four straight and five overall Grand Slam championship matches between the siblings.
"It feels great to be back. This is where it all started for me," Serena said. "I was coming here pretty much not expecting to do much. Winning my first Grand Slam in three years was great. After that I gained a lot of confidence, so for me, Roland Garros is really really special."
Since just before her triumph here, Serena has won nine titles, rose to No. 1 in the world by reaching the Wimbledon final and became only the fifth woman in history to hold all four major singles crowns at one time by capturing the Australian Open in January.
Although many - including Serena herself - have dubbed her brilliant achievement as a "Serena Slam," the 21-year-old will have to win the next three majors in order to record a true calendar-year Grand Slam - the first in singles since Steffi Graf did it in 1988.
Serena, who has lost just two matches while winning three titles this year, begins that quest Monday against Rittner, a loser in their only prior meeting.
"It's good in a way, because I just got the feel of what I need to do and some things I might want to work on," Serena said of her losses. "It makes me realize that everybody really wants to be No. 1, and it shows me how my game matches up against theirs."
The two women who have beaten Williams this season are in action as fourth seed Justine Henin-Hardenne of Belgium plays Patricia Wartusch of Austria and No. 5 Amelie Mauresmo of France battles countrywoman Virginie Razzano.
Henin-Hardenne defeated Serena in the final at Charleston and went on to claim her third title of the year at Berlin earlier this month.
The 20-year-old reached her first Grand Slam semifinal of her career here in 2001 but lost to compatiot Kim Clijsters in three sets. A month later, Henin-Hardenne appeared in her first major final at Wimbledon, where she lost to Venus Williams.
Mauresmo tagged Serena with her second loss two weeks ago in the semifinals at Rome before losing the final to Clijsters. She did win a warm-up event in Warsaw as Venus retired in the final with an abdominal strain.
Also Monday, ninth seed Daniela Hantuchova of Slovakia plays Alina Jidkova of Russia; eighth-seeded American Chanda Rubin faces Slovakian Henrieta Nagyova; and No. 11 Anastasia Myskina meets fellow Russian Dinara Safina, who is making her Roland Garros debut.
American Ashley Harkleroad and Russian teen-ager Maria Sharapova are two other noted youngsters making their first professional appearance at the French Open. Harkleroad takes on Japan's Saori Obata and Sharapova, a qualifier, squares off against Spain's Magui Serna.
Three former men's champions play their first-round matches Monday.
Second seed and 1999 winner Andre Agassi goes against Slovakian Karol Beck. Making his 15th appearance at the French Open, the 33-year-old American has a chance at a Grand Slam himself after destroying the field at Melbourne for his eighth career major.
Agassi, who briefly regained the No. 1 ranking from Lleyton Hewitt this month, has won three tournaments this year, but has played sparingly on clay. He claimed the U.S. Men's Clay Court Championships at Houston on green clay in April and lost his only European red clay match at the Rome Masters earlier this month.
Fourth seed Carlos Moya of Spain, the 1998 champion, plays Italian lucky loser Filippo Volandri. Moya won claycourt titles this year at Buenos Aires and Barcelona but has struggled in the last three weeks. He went a combined 4-4 at the Rome Masters, Hamburg Masters and the World Team Cup.
The other former winner here, No. 17 Yevgeny Kafelnikov of Russia, plays Julien Boutter of France.
Kafelnikov is having his best claycourt campaign since he triumphed here in 1996. The 29-year-old has won 10 of his last 14 matches, reaching the quarterfinals at Estoril and the semifinals at Munich and Rome.
Federer, who lost in the first round here last year, won Munich in April without dropping a set and extended his clay winning streak to 10 matches by reaching the final at Rome. He has a five-match winning streak in France after capturing the title in Marseille in February.
One of the hottest players on the circuit, No. 7 Guillermo Coria of Argentina, takes on Andre Sa of Brazil. A former junior champion here in 1999, Coria has won 14 of his last 17 matches. He reached the final at the Monte Carlo Masters and at Buenos Aires before claiming the Hamburg Masters.
Also, No. 10 Paradorn Srichaphan of Thailand meets Dominik Hrbaty of Slovakia; Australian Open finalist Rainer Schuettler of Germany clashes with American Cecil Mamiit; two-time runner-up Alex Corretja encounters fellow Spaniard Galo Blanco; and No. 24 James Blake squares off against Taylor Dent in a battle of Americans.