Australian Open: Day 5

Novak Djokovic of Serbia hits a backhand return to compatriot Viktor Troicki during their third-round match Friday at Melbourne Park. Troicki retired with stomach problems after Djokovic won the first set.

Djokovic grimaces in mock pain as he is given a ballroom dancing lesson on a outer court after his victory over Troicki by Kim Johnson of Dancing with the Stars .

Victoria Azarenka of Belarus prepares to serve during her third-round match against South Africa's Channelle Scheepers. Azarenka won 6-3, 6-3.

A general view of Margaret Court Arena on Friday afternoon.

Caroline Wozniacki of Denmark serves to Dominika Cibulkova of Slovakia during their third-round match. Wozniacki won 6-4, 6-3.

Roger Federer serves to Belgium's Xavier Malisse during their third-round match. Federer won 6-3, 6-3, 6-1.

Officials assess the court surface at Hisense Arena after reports that the ball was not bouncing properly.

Tomas Berdych of the Czech Republic plays a forehand in his third-round match against Richard Gasquet of France. Berdych won 6-2, 7-6(3), 6-2.

Young spectators at Melbourne Park show their support for the host country.

Andy Murray of Great Britain plays a forehand on the practice court during his day off. He faces 32nd-seeded Guillermo Garcia-Lopez on Saturday in the fourth round.

Russia's Svetlana Kuznetsova celebrates during her match against Belgium's Justine Henin. Kuznetsova won 6-4, 7-6(8).

Henin serves to Kuznetsova during their third-round match.

General view of Hisense Arena during the third-round match between Andy Roddick (bottom) and Robin Haase of the Netherlands. Roddick won 2-6, 7-6(2), 6-2, 6-2.

Spain's Nicolas Almagro makes a backhand return to Croatia's Ivan Ljubicic during their third-round match. Almagro won 6-4, 7-6(8), 6-3.

Italy's Francesca Schiavone celebrates a point win during her third-round match against Romania's Monica Hiculescu. Schiavone won 6-0, 7-6(2).

Maria Sharapova of Russia hits a return to Julia Goerges of Germany during their third-round match. Sharapova rallied for the 4-6, 6-4, 6-4 win.

Venus Williams played just seven points against 30th-seeded Andrea Petkovic before withdrawing due to injury.

France's Gael Monfils plays a shot back between his legs during his third-round match against Switzerland's Stanislas Wawrinka on Friday night. Wawrinka won 7-6(4), 6-2, 6-3.

Wawrinka celebrates match point against Monfils. The Swiss advances to face Andy Roddick in the fourth round on Sunday.

Monfils reacts to a line call during Friday's match with Wawrinka.