By Julien Pretot
PARIS (Reuters) - World number one Caroline Wozniacki suffered a humiliating loss in the French Open third round and Samantha Stosur joined her at the exit door on a gloomy Friday for women's tennis.
Roger Federer and David Ferrer remained on course to meet in the men's singles and the eagerly anticipated clash between Novak Djokovic and Juan Martin del Potro was interrupted by bad light with the duo locked at one-set all.
Wozniacki was thrashed 6-1 6-3 by Slovakian 28th seed Daniela Hantuchova, following world number two Kim Clijsters out as the top two seeds failed to advance past the third round at Roland Garros for the first time since 1971.
Local favorite Richard Gasquet dug deep to beat Brazilian 23rd seed Thomaz Bellucci 6-2 6-3 3-6 6-3 and fellow Frenchman Jo-Wilfried Tsonga lost a four-hour tussle with Swiss Stanislas Wawrinka 4-6 6-7 7-6 6-2 6-3.
There was nothing battling about Wozniacki's display, the Dane looking completely out of sorts under threatening skies on Court Suzanne Lenglen as she fell 6-1 4-0 behind in less than an hour.
Heading for an embarrassingly one-sided loss, Wozniacki broke back but Hantuchova ended her opponent's ordeal after 73 minutes.
Australian Stosur, last year's runner-up, could not locate her usual high-kicking serve and punishing forehand as she suffered a 6-4 1-6 6-3 defeat by Argentine world number 51 Gisela Dulko.
Russian third seed Vera Zvonareva saved the women's game from more embarrassment by beating Australian Anastasia Rodionova 6-2 6-3.
Defending champion Francesca Schiavone also started slowly but the Italian fifth seed fought back against Chinese Peng Shuai who was forced to quit because of breathing problems while trailing 6-3 1-2.
World number three Federer continued his smooth progress through the tournament in the shadow of Djokovic and Rafael Nadal, dumping Serbian 29th seed Janko Tipsarevic 6-1 6-4 6-3 in just 90 minutes.
"Expectations are sky high for Novak and Rafa as defending champion. That leaves me out of a pressure situation and that's no bad thing for me," Federer told reporters.
He will next face fellow Swiss Wawrinka, the 14th seed, who turned around his match against 17th-seeded Tsonga and a fervent French crowd on Philippe Chatrier.
Ferrer demolished Ukraine's Sergiy Stakhovsky 6-1 6-1 6-3 and the Spanish seventh seed, who has not dropped a set in three matches, will next face France's Gael Monfils after the ninth seed eased past Belgian Steve Darcis 6-3 6-4 7-5.
Frenchwoman Marion Bartoli beat German prospect Julia Goerges after dropping the first set for the third time in a row and former champion Svetlana Kuztnetsova continued her fine run with a 6-0 6-4 rout of Canada's Rebecca Marino.
(Editing by Ed Osmond)