Australian Open: Top seeds Djokovic, Serena advance to last 16

Wimbledon champion Kvitova falls in an otherwise uneventful day

MELBOURNE: Fired-up top seed Novak Djokovic powered into the Australian Open fourth round on Saturday, joining sizzling fellow world number one Serena Williams as Wimbledon champion Petra Kvitova was sent packing.

The Serb, whose chances of a fifth Australian crown have vastly improved after Roger Federer's shock exit on Friday, ground down tenacious Spaniard Fernando Verdasco 7-6 (10/8), 6-3, 6-4.

Djokovic said he was highly motivated and over the virus that hampered his lead up to the season's opening Grand Slam. "He [Verdasco] was a former top-10 player, somebody that loves playing a powerful game on the big stage. I'm glad to go through in straight sets," he said.

Serena, vying for a sixth Australian title and the first since 2010, was slow to find her groove against 26th-ranked Ukrainian Elina Svitolina, going down 6-4 in the first set. But she shook off the cobwebs under the blazing sun on Rod Laver Arena to rattle through the next two sets 6-2, 6-0.

It keeps alive her quest to add a 19th Grand Slam title, which would take her to clear second on the all-time Open Era Grand Slam winners list.

She currently has 18 alongside Chris Evert and Martina Navratilova and is four behind Steffi Graf's 22.

"When in doubt, just start running as fast as you can, that's what [my sister] Venus always told me," said Serena, whose world number one ranking is on the line if she fails to win the tournament.

Serena will now face Spain's Garbine Muguruza, who beat Switzerland's Timea Bacsinszky 6-3, 4-6, 6-0.

Venus, Azarenka, Wawrinka through

Meanwhile, sister Venus Williams rallied from behind to defeat Camila Giorgi of Italy 4-6, 7-6 (7/3), 6-1 to make the second week of a Grand Slam for the first time since Wimbledon 2011, setting up a fourth round clash with dangerous Pole Agnieszka Radwanska.

But there was heartbreak for Kvitova, a semi-finalist in 2012, as Lindsay Davenport-coached American teen Madison Keys pulled off a big 6-4, 7-5 upset.

"My hands are still shaking. Right now I can't even process this," said Keys, who set up an all-American fourth round showdown with Madison Brengle.

Victoria Azarenka also kept going, continuing her impressive comeback by downing Czech 25th seed Barbora Zahlavova Strycova 6-4, 6-4 to set up a clash with last year's beaten finalist Dominika Cibulkova.

Defending men's champion Stan Wawrinka, who beat Rafael Nadal in the final last year, could meet Djokovic in the semi-finals and stayed on track with a 6-4, 6-2, 6-4 victory over Finland's Jarkko Nieminen.

The Swiss, who was always in control, was pleased with his progress.

"It's been three really good matches, I think my game is there and I'm really happy to get through again," said Wawrinka, who will now meet Spain's Guillermo Garcia-Lopez.

Eighth seed Canadian Milos Raonic also went through as did Japan's fifth seed Kei Nishikori.

 
Like Sports on Facebook, follow @ETribuneSports on Twitter to stay informed and join in the conversation.