By Julien Pretot
PARIS (Reuters) - Third seed Agnieszka Radwanska was knocked out of the French Open 6-4 6-4 by unseeded Croatian Ajla Tomljanovic in the third round on Friday, becoming the latest victim of a new generation of talent sweeping through the draw.
The top three seeds have now been sent packing following the first-round exit of Chinese Li Na and the second-round elimination of defending champion and world No.1 Serena Williams of the United States.
It is the first time since tennis turned professional in 1968 that the top three seeds in the women's draw have failed to qualify for the fourth round of a grand slam.
Australian Open champion Li was knocked out in the first round by France's 21-year-old Kristina Mladenovic, ranked 103, and Williams was beaten in the second round by 20-year-old Garbine Muguruza of Spain.
"After seeing the two first seeds go out, you kind of feel you can do this, too," said the 21-year-old Tomljanovic.
"I grew up with these girls who are beating them. I went into the stadium for the first time, and she kind of feels like home there, because she's been there a lot more than I have.
"I went out there, and inside I really thought I could win. I think that showed and it is why I won."
Radwanska's defeat was another boost for 2012 champion and last year's runner-up Maria Sharapova, who takes on unseeded Argentine Paula Ormaechea later on court Philippe Chatrier.
Poland's Radwanska reached the Australian Open semi-finals in January but played poorly on Friday, causing the world No. 72 few problems.
"This year I've been in a few situations when I did not execute and this time I wanted to make it right," the Florida-based Tomljanovic said.
Tomljanovic unsettled Radwanska with sliced backhands and opened a 5-1 lead after breaking serve twice. The Pole pulled one back for 5-3 with a forehand winner but a lob that sailed long handed Tomljanovic the opening set.
She kept her composure, mixing it up with drop shots to break in the first game of the second set and holding serve throughout.
Tomljanovic, who had failed to qualify for Roland Garros every year since 2010, will next meet American teenager Taylor Townsend or Spanish 14th seed Carla Suarez Navarro.
She ended the contest on the first match point when Radwanska hit long in yet another unforced error.
Radwanska summed up the defeat by saying: "I don't think it was my day today."
Tomljanovic was joined in the fourth round by former finalist Samantha Stosur of Australia, who beat Slovakian ninth seed Dominika Cibulkova 6-4 6-4.
"I'm very happy with my tennis, today was definitely the toughest match. I am very happy to get through in straight sets," said the 2011 U.S. Open champion who now has a 5-0 record against Cibulkova.
Later on Friday, Serbian second seed Novak Djokovic plays Croatian 25th seed Marin Cilic on court Suzanne Lenglen and 17-times grand slam winner Roger Federer, the fourth seed, is up against Russian Dmitry Tursunov.
(Reporting by Julien Pretot; Editing by Robert Woodward, Ed Osmond and Toby Davis)