Azarenka, Federer Reach Australian Open 4th Round; Del Potro Out

Defending champion Victoria Azarenka was pushed to three sets by an injured opponent before reaching the fourth round of the Australian Open along with Serena Williams, Roger Federer and Andy Murray. No. 6 Juan Martin Del Potro became the highest seed to be eliminated.

With the third round complete, Del Potro is the only one of the top eight men’s seeds who failed to make it to the last 16 at the season-opening Grand Slam tournament. Six of the eight leading women advanced to the second week.

Top-seeded Azarenka of Belarus, who won her first major title at Melbourne Park 12 months ago, came back from a break down in the third set to beat 63rd-ranked Jamie Hampton of the U.S. 6-4, 4-6, 6-2 yesterday at Rod Laver Arena.

“These kind of matches sometimes bring better things for you in the future,” Azarenka, who was outhit by 41 winners to 17, told reporters. “Because winning ugly always means that you overcome something, that you weren’t feeling great, you weren’t feeling all your shots. From here, I can only go up.”

Hampton, who took a medical timeout before holding her serve to win the second set and appeared to wince from pain when striking the ball for the rest of the match, broke for a 2-1 lead in the deciding set before Azarenka won the next five games. Hampton said afterward that she has two herniated disks that require her back to be taped up before each match.

Azarenka, 23, will play Elena Vesnina tomorrow for a place in the quarterfinals after the world No. 47 from Russia outlasted No. 16 seed Roberta Vinci of Italy 4-6, 7-6 (7-4), 6-4 in a two hour, 53-minute contest.

Djokovic, Sharapova

Today, men’s No. 1 seed Novak Djokovic of Serbia continues his bid for a third straight Australian Open title against Switzerland’s Stanislas Wawrinka, the 15th seed. Women’s No. 2 Maria Sharapova of Russia faces Kirsten Flipkens of Belgium.

Williams, the No. 3 seed from the U.S., fell behind 0-3 in the second set yesterday before completing a 6-1, 6-3 victory over Ayumi Morita of Japan to extend her winning run to 19 matches. She said the ankle she rolled during her opening match was improving every day and she’s able to practice hard.

“I feel today was actually a really good match for me,” said Williams, who fired a 207 kilometer-per-hour (129 mile-per-hour) ace to match her mark for the fastest serve of the women’s draw. “I was involved in a lot of longer points, something I definitely wanted.”

The 31-year-old Williams, who lifted her tally of major titles to 15 by winning Wimbledon and the U.S. Open last year, will next face Maria Kirilenko after the 14th-seeded Russian beat Yanina Wickmayer of Belgium 7-6 (7-4), 6-3.

Federer Fires

Record 17-time Grand Slam singles champion Federer ended Australian Bernard Tomic’s unbeaten start to 2013 with a 6-4, 7-6 (7-5), 6-1 victory at Rod Laver Arena, where he’s won four titles. The Swiss, who fought back from 1-4 down in the tiebreaker, next faces 13th-seeded Milos Raonic, who beat No. 17 seed Philipp Kohlschreiber of Germany in straight sets to tie his best Grand Slam result by reaching the last 16.

“He’s got a monster of a serve,” Federer said of Canada’s Raonic, who’s sent down a tournament-leading 71 aces including one at 228 kilometers-per-hour that tied for fastest on the men’s side. “I’m looking forward to a tough one.”

Del Potro, the 2009 U.S. Open champion from Argentina, was beaten 6-3, 6-3, 6-7 (3-7), 3-6, 6-3 by the unseeded Jeremy Chardy of France. The 36th-ranked Chardy will next face 21st-seeded Andreas Seppi, who outlasted No. 12 Marin Cilic of Croatia in five sets.

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Third-seeded Murray of Britain defeated Lithuanian qualifier Ricardas Berankis 6-3, 6-4, 7-5 to extend his winning run at Grand Slams to 10 matches following his breakthrough title at the U.S. Open in September.

Murray will next play No. 14 seed Gilles Simon, who defeated fellow Frenchman Gael Monfils in a five-set match that lasted four hours, 43 minutes and finished at 12:31 a.m. local time. The final set alone took 94 minutes.

“I was ready for this kind of fight,” Simon said after winning 6-4, 6-4, 4-6, 1-6, 8-6. “I really need to recover from this one before I think about Andy.”

No. 7 seed Jo-Wilfried Tsonga, the 2008 runner-up in Melbourne, beat Blaz Kavcic of Slovenia to set up an all-French matchup with ninth-seeded Richard Gasquet.

In other women’s results, two-time major winner Svetlana Kuznetsova of Russia advanced with a 6-2, 4-6, 6-3 win over Spaniard Carla Suarez Navarro and will next play former world No. 1 Caroline Wozniacki of Denmark. Sloane Stephens of the U.S. beat Britain’s Laura Robson 7-5, 6-3 in a matchup between the only teenagers left in the women’s draw.

The run of 42-year-old Kimiko Date-Krumm ended with a 6-2, 7-6 (7-3) defeat to Bojana Jovanovski, a player half her age. Japan’s Date-Krumm was the oldest woman to reach the third round of a Grand Slam since 1979.

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