The little chats Serena Williams likes to have with herself on the court took a decidedly negative turn at the Australian Open today after the No. 3 seed kept dumping backhand after backhand into the net against Russian Elena Likhovtseva.

Williams muttered to herself, she groaned--she even tried to give herself a pep talk--but nothing coming out of her mouth could make up for the poor strokes coming from her racket as she fell, 6-3, 6-3, in the fourth round at Melbourne Park.

"I couldn't stop making errors," said a dispirited Williams, sitting afterward with her arms folded over her chest and a baseball cap pulled low over her eyes. "I wouldn't do anything right. I just wouldn't do anything right this match."

This was the first tournament Williams had played in three months, and the rust she had accumulated during her layoff showed in most of her matches here. Williams also didn't help herself by arriving in Australia just three days before the tournament began, although she said today that her trouble adjusting to the 16-hour time difference from her native Florida "was no excuse."

A strained back that had been bothering Williams at the start of the tournament was also fine, she said--it was her brain, not her back, that was bothering her today.

"I just started making too many errors, and maybe I started thinking too far into the match," said Williams, who had been on course to meet top seed Martina Hingis in the semifinals. "A lot goes wrong when you are playing in your head."

Williams had started the match strongly, taking a 3-1 lead after breaking Likhovtseva's serve, but when her game began to fall apart, Likhovtseva, the No. 16 seed, took advantage. Suddenly, Williams couldn't get a ball over the net, and Likhovtseva won the first set. Likhovtseva then stormed out to a 3-0 lead in the second set, although Williams was able to win back an early break and even held two break points on Likhovtseva's serve.

For a moment, it appeared Williams was working her way back into the match, the same way she had in her first two matches after suffering early lapses. But each time Likhovtseva gave Williams an opportunity to break, Williams answered with an error, preventing her from gaining any control over the match. Likhovtseva offered Williams one final chance in the last game, showing some nerves and wasting two match points. Williams appeared equally fumbling, however, and she delivered one last backhand into the net to seal the match.

"I couldn't find my rhythm through the whole match," she said. "It's strange. I was hitting and moving well in practice, and wasn't making any errors, and then out there I just couldn't find my rhythm."

The morning was much kinder to No. 13 seed Arantxa Sanchez-Vicario, who stormed back from an early deficit to upset No. 6 Barbara Schett, 1-6, 6-0, 7-5. Andre Agassi also had a pleasant day, basking in his Sunday night win over Australian Mark Philippoussis.

The 6-4, 7-6 (7-4), 5-7, 6-3 victory came relatively easy to the top-seeded Agassi, but Philippoussis did not take it so well, smashing his racket beyond recognition after losing a second-set tiebreaker. "I had to let some frustration out, otherwise I was going to kill someone," Philippoussis explained later. "Better the racket."

Agassi was a little stunned to see Philippoussis's racket folded into such a shape--"the guy can make a racket look like a toothpick," he said--but he never lost confidence in his game, withstanding Philippoussis's 25 aces and lulling the 23-year-old into some long rallies that were clearly to Agassi's advantage.

Third-seeded Pete Sampras also won his fourth-round match, defeating Slava Dosedel, 6-1, 6-2, 3-6, 6-1, and Tennessee native Chris Woodruff was a surprise victor against No. 11 seed Tim Henman, 7-5, 1-6, 6-4, 3-6, 7-5. Sampras said he was "a little annoyed" to lose the third set to Dosedel, but he was much more pleased overall than after his last match, in which he lost the first two sets. In that match, he seemed uncomfortable even with the dimensions of Rod Laver Arena, hitting balls long, high and wide, but a practice Saturday that involved "working on keeping the ball in the court" helped him get into a better rhythm by the time Sunday's match rolled around.

"I worked on a few things and it paid off--just being a little more deliberate with what I am trying to do," Sampras said. "I was a little bit more focused on what I was trying to do and felt a little more comfortable playing today."

Sampras took the court just after Agassi left, and while much of the crowd at Melbourne Park stayed for his match, offering polite applause at all the appropriate intervals, the fans seemed sapped from cheering on their local hero against the top-seeded American. Philippoussis has been serving the fastest balls of the tournament, and Australians were eager to see how he would stand up against Agassi's illustrious return game. Unfortunately for them, he didn't.

"He's 29 years old and playing the best tennis of his life--it's quite incredible," Philippoussis said of Agassi.

"He is the cleanest hitter of a ball of any person I have played, and he is not really a nice player to meet early on in tournaments, I will put it that way."

Australian Open

When: Through Jan. 30.

Where: Melbourne Park, Melbourne, Australia.

TV: ESPN, ESPN2.

Results for Seeded Players: Men's fourth round--Andre Agassi (1), United States, def. Mark Philippoussis (16), Australia, 6-4, 7-6 (7-4), 5-7, 6-3; Pete Sampras (3), United States, def. Slava Dosedel, Czech Republic, 6-1, 6-2, 3-6, 6-1; Nicolas Kiefer (4), Germany, def. Wayne Ferreira, South Africa, 6-3, 6-4, 6-2; Chris Woodruff, United States, def. Tim Henman (11), Britain, 7-5, 1-6, 6-4, 3-6, 7-5.

Women's fourth round--Elena Likhovtseva (16), Russia, def. Serena Williams (3), United States, 6-3, 6-3; Conchita Martinez (10), Spain, def. Kristina Brandi, United States, 6-1, 6-1; Arantxa Sanchez-Vicario (13), Spain, def. Barbara Schett (6), Austria, 1-6, 6-0, 7-5.