PARIS -- Kim Clijsters felt sluggish, her game lagged and what followed was a stunning loss at the French Open.

Last year's runner-up, Clijsters made 59 unforced errors Friday and was ousted in the third round by the world's No. 87 player.

``I just felt tired. My whole body just felt a little heavier. That's not the reason,'' Clijsters said after she was upset 6-4, 6-0 by Clarisa Fernandez, a lanky left-hander from Argentina.

``I just didn't play well. I just didn't move forward enough when I had chances to finish off points quicker,'' she added.

No. 2 Venus Williams and No. 6 Monica Seles also moved on to the round of 16.

And tennis wasn't the only thing on the minds of those roaming the grounds of the picturesque facility. Cheers could be heard while France's soccer team played -- and lost -- to Senegal in the first round of the World Cup.

Williams easily beat No. 31 Rita Grande 6-1, 6-4 and will meet fellow American Chanda Rubin, who routed No. 23 Anne Kremer 6-1, 6-0.

Seles rolled past Ludmila Cervanova 6-2, 6-2, setting up a round of 16 matchup against 11th-seeded Daniela Hantuchova, who beat Tatiana Panova 6-3, 6-1. No. 10 Amelie Mauresmo routed Eva Bes 6-1, 6-1 and faces Paola Suarez, who beat No. 27 Nathalie Dechy 6-4, 4-6, 7-5.

Clijsters, fourth-seeded, entered the tournament as one of the favorites after losing a thrilling 12-10 third-set tiebreaker to Jennifer Capriati in last year's final.

Playing in her first French Open, Fernandez clinched her victory on the sixth match point when Clijsters sent a forehand into the net.

Clijsters made at least the quarterfinals in the four previous Grand Slam tournaments, including the semis at the Australian Open in January.

``I had a lot of confidence in myself,'' Fernandez said. ``I didn't really look at her ranking. I knew she was one of the best players around.''

Fernandez's next opponent is 13th-seeded Elena Dementieva, who beat Rossana Neffa-de los Rios 6-3, 6-0.

Williams rolled to victory in just 52 minutes.

``She dictated everything. I just did what I could to get the ball back. You hit a great shot and she takes two steps and is there,'' Grande said.

``It's nice not being on the court too long. Anything can happen on clay,'' said Williams, who's lost just 12 games in three matches.

Asked if she'd scouted Williams, Rubin -- who's coming back from knee surgery -- said not exactly.

``She's been winning so quickly and so easily, I'm probably not up at that time,'' Rubin said.