By John Pye
The Associated Press

MELBOURNE, Australia - Defending champion Andre Agassi advanced to the Australian Open quarterfinals Sunday, beating 13th-seeded Paradorn Srichaphan 7-6 (3), 6-3, 6-4.

Agassi won his 25th consecutive match in the season-opening major and improved to 205-45 in 250 career Grand Slam matches. He also avenged a loss to Paradorn in the second round of Wimbledon in 2002, their only previous contest.

"I came out here with a lot of respect for his firepower," Agassi said. "I had to make sure I was dictating play and not backing off - it was good."

The 33-year-old American, seeking his fifth Australian Open title, set up a quarterfinal match against ninth-seeded Sebastien Grosjean of France, a 6-4, 3-6, 6-4, 6-1 winner over 32nd-seeded Robby Ginepri of the United States.

In late men's matches, No. 1 Andy Roddick faced No. 16 Sjeng Schalken of Netherlands, and Russia's Marat Safin played American James Blake.

In women's play, top-ranked Justine Henin-Hardenne had to save a set point before advancing to the quarterfinals with a 6-1, 7-6 (5) victory over Italian qualifier Mara Santangelo.

She will play 2000 champion Lindsay Davenport in the quarterfinals, while fourth-seeded Amelie Mauresmo of France advanced to face 32nd-seeded Fabiola Zuluaga, the first Colombian woman to reach a Grand Slam quarterfinal.

Davenport won the last eight points in her 6-1, 6-3 victory over 11th-seeded Vera Zvonareva of Russia.

Mauresmo beat Australia's Alicia Molik 7-5, 7-5, and Zuluaga defeated Hungary's Aniko Kapros 6-4, 6-2.

Agassi saved five set points in the first, three on serve in the 10th game and another two in the 12th before forcing a tiebreaker with an ace. He took four of the first five points in the tiebreaker, and won when Paradorn's backhand return landed long.

"I had to fight off a few there," he said. "The set was imbalanced the whole way. I mean, I felt like I could have blown the first set open a lot earlier, having some chances.

"And then when I didn't put that away, he hung in there tough, and I had to come up with some pretty good tennis late in the set to pull it out."

Paradorn rolled his ankle in the fifth game of the third set, but didn't make it an excuse. What hurt more, he said, was wasted opportunities in the first set.

"If I took my time a little more, it could have been a little bit different," he said.

Agassi had eight fewer winners (31-39) but 16 fewer unforced errors (28-44) than Paradorn.

Henin-Hardenne raced through the first set in 28 minutes, but started making uncharacteristic mistakes on her backhand in the second and dropped serve to trail 1-3. She saved four break points in the seventh game, and saved a set point in the 10th game before breaking to level at 5-5.

Santangelo, ranked No. 129, held serve to force the tiebreaker. She fell behind 4-1, but rallied to tie it at 4 with a volley that had her skipping with delight back to the baseline.

But Henin-Hardenne regained control, ending the match with a forehand pass that just clipped the line. She finished with 24 winners and 29 unforced errors.

"It wasn't an easy match," she said. "I won the first set pretty easily, with a lot of intensity, then, at 1-all in the second, the intensity came down a little and she just took her chances - it was a big fight in the second set."

Henin-Hardenne beat Davenport in the fourth round last year, rallying from a 4-1 deficit in the deciding set and overcoming cramps to win 7-5, 5-7, 9-7.

Mauresmo struggled to beat the 40th-ranked Molik after losing only six games in the first three rounds.

"Obviously she gave me a lot of trouble," Mauresmo said. "I just really wanted to go through this one and go to the quarters."

Mauresmo, a finalist in 1999, missed the tournament last year because of injuries and said she was bothered by back trouble against Molik, but didn't think it would upset her campaign.

"I'm going to go for treatment and make sure everything is OK for the quarterfinals," she said.

With the victory, Mauresmo is assured of breaking into the top three for the first time when the next WTA Tour rankings are released. Her career high was No. 4 in October 2002.