Two-time defending champ Djokovic reaches 4th round with 17th straight win at Australian Open

MELBOURNE, Australia - Novak Djokovic didn't get all the breaks against Radek Stepanek on Friday at the Australian Open. The top-ranked Serb, however, remains virtually unbeatable Down Under.

Djokovic beat Stepanek 6-4, 6-3, 7-5 to advance to the fourth round and extend his winning streak to 17 matches at the Australian Open.

Djokovic broke the 34th-ranked Stepanek late in each set, but was troubled at times against a wily veteran who mixed up the tempo with a lot of serve-and-volley and some unorthodox shot-making.

"Absolutely it was great. Great match and great fun," Djokovic said. "It's always tricky to play Radek. He's a talented player. Skilful player."

Told about the statistics — Stepanek won 36 of the 67 points he played at the net — Djokovic wasn't surprised at all.

"He's skilful on the net and he was not giving me a lot of rhythm — he was changing up the pace on the ball," Djokovic said. "Nowadays everything is based on the baseline. It's nice to see somebody coming to the net."

Stepanek had Djokovic smiling and acknowledging his winners on some points, frustrated him on others with his constant, stay-in-the-point defence, and even had chair umpire Carlos Bernardes grinning with his over-the-shoulder winner to save one match point near the end.

Djokovic, the two-time defending champion who also won the title at Melbourne Park in 2008, is hoping to become the first man in the Open era to win three consecutive Australian titles. He will next play either American Sam Querrey or Switzerland's Stanislaw Wawrinka in the fourth round Sunday.

Angelique Kerber survived some nervous moments before fending off American teenager Madison Keys 6-2, 7-5 in their third-round match, then got to blow out the candles on a cake to celebrate her 25th birthday.

Local organizers brought a cake onto the court for Kerber immediately after the match and the crowd at Rod Laver Arena sang "Happy Birthday." She blew out the candles and said thank you to the crowd and to the 17-year-old Keys.

"Madison is a great young player and it was very tough," said Kerber, a semifinalist last year at Wimbledon. "So happy I won today on my birthday!"

Kerber will next play No. 19 Ekaterina Makarova of Russia, who advanced after a tough 6-7 (4), 6-3, 6-4 win over 2007 Wimbledon finalist Marion Bartoli. In the fourth round last year, Makarova beat Serena Williams and was the first of only four women to best the powerful American in 2012. Kerber was the last.

Fourth-seeded Angieszka Radwanska, meanwhile, won her 12th match in a row with a 6-3, 6-1 victory over Britain's Heather Watson.

"I'm extremely happy to be playing my best tennis from the beginning of the year," said Radwanska, who won tournaments in Auckland and Sydney earlier this month. "Hopefully I'll play on the same level the rest of the tournament."

Radwanska will now meet 2008 French Open champion Ana Ivanovic, who beat Jelena Jankovic 7-5, 6-3 in a matchup featuring two Serbians who were both formerly ranked No. 1.

Sixth-seeded Li Na advanced with a 6-4, 6-1 win over No. 27 Sorana Cirstea of Romania and will next play No. 18 Julia Goerges, who prevented an all-China fourth-round encounter by beating Zheng Jie 6-3, 1-6, 7-5 .

Li won the 2011 French Open just a few months after reaching the final at the Australian Open. Reigning French Open champion Maria Sharapova was playing seven-time major winner Venus Williams in a night match.

After soaring to 106 degrees on day four, the temperature dropped into the mid-70s on Friday, and light rain briefly interrupted play on some courts.

Roger Federer has won four Australian Open titles among his 17 majors, and is ordinarily one of the most popular athletes in Australia. The only problem is this: His 6-3, 6-4, 6-4 win over Nikolay Davydenko on Thursday night set Federer on course for a third-round match against Bernard Tomic, the last remaining Australian in the men's or women's draws.

The 20-year-old Tomic beat German qualifier Daniel Brands 6-7 (4), 7-5, 7-6 (3), 7-6 (8).

"I don't think it matters whether he's the last Australian or 10 more," Federer said. "There's always excitement about Aussies playing here. I played him here last year. The crowd was great. I expect something similar. If it's not, if it's totally for him, that's fine, too. I'm always excited when the crowd gets into it."

U.S. Open champion Andy Murray advanced with a 6-2, 6-2, 6-4 win over Joao Sousa of Portugal to move into the third round, along with 2009 U.S. Open champion Juan Martin del Potro, 2008 Australian finalist Jo-Wilfried Tsonga and his fellow Frenchman Richard Gasquet, No. 13 Milos Raonic of Canada and No. 17 Philipp Kohlschreiber of Germany.

On the women's side, top-ranked Victoria Azarenka advanced and Serena Williams had an easy second-round win to ease any concern about an ankle injury that threatened to derail her bid for a third straight major title.

Also moving on were 42-year-old Kimiko Date-Krumm, former No. 1 Caroline Wozniacki and British teenager Laura Robson.