2013 Australian Open: Day 6

Maria Sharapova and Novak Djokovic earned spots in the second week of the year's opening Grand Slam tennis tournament.

Djokovic plays another Australian Open marathon

Switzerland's Roger Federer hits a forehand return to Australia's Bernard Tomic during their third round match at the Australian Open tennis championship in Melbourne, Australia, Saturday, Jan. 19, 2013. (AP Photo/Andy Wong)

Djokovic plays another Australian Open marathon

Supporters of Switzerland's Roger Federer wave a banner of support during his third round match against Australia's Bernard Tomic at the Australian Open tennis championship in Melbourne, Australia, Saturday, Jan. 19, 2013. (AP Photo/Andy Wong)

Djokovic plays another Australian Open marathon

Switzerland's Roger Federer, left, is congratulated by Australia's Bernard Tomic following their third round match at the Australian Open tennis championship in Melbourne, Australia, Saturday, Jan. 19, 2013. (AP Photo/Andrew Brownbill)

Djokovic plays another Australian Open marathon

Supporters of Australia's Bernard Tomic pose for photographers as they cheer him on while watching his third round match against Switzerland's Roger Federer on a giant screen outside the Rod Laver Arena, at the Australian Open tennis championship in Melbourne, Australia, Saturday, Jan. 19, 2013. (AP Photo/Andrew Brownbill)

Defending champ Azarenka advances to quarterfinals

Switzerland's Stanislas Wawrinka kicks a ball during his fourth round match against Serbia's Novak Djokovic at the Australian Open tennis championship in Melbourne, Australia, Sunday, Jan. 20, 2013. (AP Photo/Andrew Brownbill)

Defending champ Azarenka advances to quarterfinals

Serbia's Novak Djokovic reacts during his fourth round match against Switzerland's Stanislas Wawrinka at the Australian Open tennis championship in Melbourne, Australia, Sunday, Jan. 20, 2013. (AP Photo/Andy Wong)

2013 Australian Open - Day 7

MELBOURNE, AUSTRALIA - JANUARY 20: Maria Sharapova of Russia celebrates winning her fourth round match against Kirsten Flipkens of Belgium during day seven of the 2013 Australian Open at Melbourne Park on January 20, 2013 in Melbourne, Australia. (Photo by Cameron Spencer/Getty Images)

Maria Sharapova

Maria Sharapova avançou às quartas de final do Aberto da Austrália.

Defending champ Azarenka advances to quarterfinals

Russia's Maria Sharapova hits a forehand return to Belgium's Kirsten Flipkens during their fourth round match at the Australian Open tennis championship in Melbourne, Australia, Sunday, Jan. 20, 2013. (AP Photo/Dita Alangkara)