PARIS (AP) - Top-seeded Martina Hingis and defending champion Arantxa Sanchez-Vicario powered their way toward a possible semifinal meeting with easy third-round victories today at the French Open.

Hingis beat Kveta Hrdlickova of the Czech Republic 6-3, 6-4, helped by a double-fault from heropponent to set up triple match point.

Sanchez-Vicario beat Irina Spirlea of Romania 6-4, 6-1.

Neither player has lost a set in the first three rounds. Hingis has lost only 18 games, and Sanchez-Vicario only 12.

The two could meet in the semifinals, but first Hingis has a likely date in the quarters with Venus Williams - also in top form. The fifth-seeded Williams was to play Alicia Molik later in the day.

On Thursday, Pete Sampras made an anguished exit after failing for the 10th time to reach victory at Roland Garros, the one Grand Slam title that eludes him.

Not long after his painful, second-round loss, Sampras was asked why he didn't just throw in the towel, once and for all, and focus on the other three events.

``Say that again?'' he asked. ``Not play here?''

The question seemed to energize him.

``I would never do that,'' he said, emphasis on the word ``never.'' And again: ``That's something I would never do.'' And a moment later: ``No, I would never pass this up.''

One would think that passing up an ordeal that gets more agonizing each year would be logical.

But then, one wouldn't be using the logic Sampras uses. For him, all that counts now is what goes down in the record books.

That is why Sampras worked so hard last year to finish at No. 1, becoming the only player to do so six times in a row. He said he knew that was a record that would probably never be broken, and that is why he wanted it.

Likewise, Sampras knows he has a good chance of going down in history as the greatest player ever. But not, he thinks, if he keeps failing miserably in his quest for the one Grand Slam title to elude him.

So Sampras insists on trying, again and again, even though he feels so ill at ease on clay. Just one time, he fervently hopes, he will string seven matches together here. Once is all it takes.

``I've won all the other majors, and this is one that is my biggest challenge,'' he said after his 7-5, 1-6, 6-4, 6-3 loss to Andrei Medvedev. ``I'm hopefully going to play this game for many years, just keep on coming back and trying.''

But Sampras knows his time is limited. He is 27 now, and though that still sounds young to many, there are a whole lot of players who are younger and much more comfortable on clay.

So Sampras needs to figure out what he is doing wrong.

``I'm sitting here just after losing, thinking, 'What happened?'' he said. ``What could I have done strategy-wise?''

Sampras never looked comfortable during the match. He missed shots that normally he makes effortlessly, even his feet-in-the-air overhead. He scolded himself, and even came close to throwing his racket.

``I was very frustrated,'' Sampras explained later. But he contained himself, he said.

``I'm still boring,'' he joked, echoing a sentiment that's often voiced about him. ``Let's not forget that. But I was on the edge of breaking a few sticks.''

It must have been doubly frustrating to feel himself going down on the same court, in the same round as he did last year, to 97th-ranked Ramon Delgado of Paraguay. At least it was to a better player: Medvedev is ranked 100th now, but at one time was fourth in the world.

Sampras' serve is usually his key weapon, to be unleashed at important moments. But in this match Sampras managed only five aces, while spraying 61 unforced errors.

Medvedev, on the other hand, merely hit accurate, deep groundstrokes, and served well enough to score 11 aces.

The Ukrainian, who grew up playing on clay, tried to downplay the significance of his win, and paid a great tribute to Sampras.

``I think he is the greatest player on earth that's ever picked up a tennis racket. But I don't think he played his best tennis today,'' Medvedev said.

And then, with obvious understatement: ``It's not his favorite surface.''