MELBOURNE, Australia — Lleyton Hewitt beat Juan Ignacio Chela in an Australian Open match seemingly full of spit and venom.

Chela became angry yesterday when he thought Hewitt's loud cry of "Come on!" was a bit too much of a reaction after Chela's unforced error that resulted in triple break point in the fifth game of the fourth set.

He drove his next serve at Hewitt, even though it was during an important part of the match. Hewitt converted the break and Chela appeared to spit toward the Australian when the players were switching sides.

"He spat in my direction," said Hewitt, who won the third-round match 6-2, 4-6, 6-1, 6-4. "It's unfortunate because we were having a dogfight match out there. We're both competitive blokes. We were going for it.

"It's sad that something like that happens. But, you know, he apologized to me at the net when we shook hands and I said, 'Just forget about it, mate.' "

Chela said he didn't spit at Hewitt.

"I did spit, but I was not spitting at him," Chela said. "He thought that I did, though, and that's why I apologized."

Tournament referee Peter Bellenger, after reviewing video of the match, fined Chela $2,000 for unsportsmanlike conduct.

Though Hewitt accepted Chela's apology on the court, an Australian newspaper, the Herald Sun, reported there was an argument in the locker room between Hewitt's coach, Roger Rasheed, and Chela and a member of his camp after Rasheed made it clear that such a gesture was unacceptable and would not be tolerated in the future.

Chela would not confirm the alleged locker-room incident.

The third-seeded Hewitt, the 2001 U.S. Open and 2002 Wimbledon champion, finished his match soon after his next opponent, Rafael Nadal, ousted American qualifier Bobby Reynolds 6-1, 6-1, 6-3.

Defending champion Roger Federer of Switzerland advanced to the quarterfinals, extending his winning streak to 25 matches with a 6-2, 6-2, 7-6 (7-4) victory over Marcos Baghdatis in the fourth round.

Federer will play four-time winner Andre Agassi of Las Vegas in a high-profile match.

Agassi beat Sweden's Joachim Johansson 6-7 (4-7), 7-6 (7-5), 7-6 (7-3), 6-4 in a 2-hour, 38-minute match. The 6-foot-6 Johansson had 51 aces, believed to be a record for a singles match at a Grand Slam event.

Agassi made 13 unforced errors. Johansson mixed 66 unforced errors with 96 winners, including aces and service winners. Johansson surpassed Richard Krajicek's mark of 49 aces in a match at the 1999 U.S. Open.

U.S. Open champion Svetlana Kuznetsova advanced, not surprisingly, by beating another Russian. Kuznetsova pounded 29 winners in a 6-4, 6-2 win over Vera Douchevina, who had five winners.

Seven Russian women made the fourth round, including Wimbledon champion Maria Sharapova.

No. 4 Sharapova, who will face No. 5 Kuznetsova next, rallied to beat 15th-seeded Silvia Farina Elia of Italy 4-6, 6-1, 6-2.

No. 2 Amelie Mauresmo of France had a 6-2, 6-4 win over Russia's Evgenia Linetskaya in a mistake-prone match with 11 service breaks. Linetskaya held serve once in the match.