Roddick sweeps his way into quarterfinals

MELBOURNE, Australia -- Andy Roddick overcame some frustrating lapses before advancing to the Australian Open quarterfinals with a 6-3, 7-6 (8), 6-1 win Monday over German qualifier Philipp Kohlschreiber.

Top-ranked Lindsay Davenport breezed into the women's quarterfinals, needing just an hour to beat No. 13 Karolina Sprem 6-2, 6-2. Sprem held serve only once in each set, while Davenport converted six of her 10 breakpoint opportunities.

Roddick, the No. 2 seed, lost just three points on his serve in the first set, but was more erratic in the second, doubling his number of unforced errors to 12 and throwing his racket to the court after sending a forehand long.

After taking the tiebreaker on consecutive errors by the 102nd-ranked Kohlschreiber, Roddick dominated the third set, breaking the German twice.

"I don't think I hit the ball as clean as I did in the first three matches," Roddick said, "I just felt like I was fighting it a little bit more.

"I'm not too concerned. I got through it OK. The good thing is I don't feel like I had my best day and we're sitting here talking about a three-set win. So that's good."

Roddick will face the winner of the fourth-round match between Argentina's Guillermo Canas and Russia's Nikolay Davydenko. Roddick could face No. 3 Lleyton Hewitt in the semifinals. Hewitt was playing Spain's Rafael Nadal later Monday in the fourth round.

In other women's action, Russia's Elena Dementieva, a finalist at the French and U.S. Opens last year, led 12th-seeded Patty Schnyder by a set and two breaks before losing 6-7 (6), 7-6 (4), 6-2.

The match was riddled with 116 unforced errors, sixth-ranked Dementieva contributing 61 of those. She saved a match point with a convincing forehand winner but then gave Schnyder another with a double fault and lost the match when she dumped a forehand into the net.

Schnyder was a surprise semifinalist here last year, beating three seeded players in straight sets before losing to eventual runnerup Kim Clijsters in the penultimate round.

French Open champion Anastasia Myskina was playing Nathalie Dechy later Monday, aiming to be the third of Russia's three Grand Slam title holders into the women's quarterfinals.

In an all-Argentinian fourth-round men's match later Monday, sixth-ranked Guillermo Coria faces No. 9 David Nalbandian, a quarterfinalist at Melbourne Park the last two years.

At times, Roddick lacked intensity against the lowest-ranked man remaining in the draw, relying on his big serve for motivation. He served 15 aces, many just when games were looking stale.

Roddick might have been conserving energy for the quarterfinals. In 2003, he beat Morocco's Younes El Aynaoui 21-19 in the fifth set of a 5-hour marathon. It was the longest fifth set, in games, in men's singles at a Grand Slam tournament.

In what's shaping as an Australian Open classic, top-ranked and defending champion Roger Federer and four-time winner Andre Agassi will meet in the quarterfinals.

On Sunday, prolific serve returner Agassi was almost dumbfounded by the unrelenting power of Joachim Johansson's service game in the fourth round.

Agassi weathered a record 51 aces by the 6-foot-6 Swede to win 6-7 (4), 7-6 (5), 7-6 (3) 6-4 and advance.

"It's a phenomenal weapon he has," Agassi said. "Joachim was hitting the ball so big -- what can you do but react?"

Johansson beat Richard Krajicek's tour record of 49 aces, set in a quarterfinal loss to Yevgeny Kafelnikov at the 1999 U.S. Open.

Federer, who is on a career-best, 25-match winning streak, had a victory that was far less complicated than Agassi's -- 6-2, 6-2, 7-6 (4) over Cypriot qualifier Marcos Baghdatis.

Federer, whose 11 titles in 2004 included three majors, has won 48 of 50 matches. The defending champion hasn't lost since the second round at the Athens Olympics and has a four-match winning streak against Agassi.

Marat Safin, who lost to Federer in last year's Australian final, converted just one of his 18 break-point chances in a fiery 4-6, 7-6 (1), 7-6 (5), 7-6 (2) win over Olivier Rochus.

He drew a code violation for spiking his racket after wasting three break-point opportunities in the third set. After the caution from the umpire, he belted the broken racket three more times on a cooler, leaving marks on the top.

He closed with two aces, taking his total to 29 for the match. He next faces Slovakia's Dominik Hrbaty, who beat the other Swedish Johannson in the draw -- 2002 Australian Open champion Thomas Johansson -- 7-5, 6-3, 6-1.

Two of Russia's Grand Slam champions will face off in the quarterfinals. U.S. Open champion Svetlana Kuznetsova beat fellow Russian Vera Douchevina and will face Wimbledon winner Maria Sharapova, who rallied to beat Italy's Silvia Farina Elia 4-6, 6-1, 6-2.

Seventh-seeded Serena Williams, who won the Australian Open in 2003 but didn't return last year because of a knee injury, beat No. 11 Nadia Petrova 6-1, 3-6, 6-3. Second-seeded Amelie Mauresmo topped Evgenia Linetskaya 6-2, 6-4.