The 101st edition of the Australian Open tennis tournament is under way at Melbourne Park in Australia. This is the first Grand Slam event of the year, held until January 27. Above: A fan with a painted face attends the Australian Open in Melbourne. Picture: Daniel Munoz/Reuters

Yanina Wickmayer of Belgium throws her racket after missing a point during her women’s singles match against Maria Kirilenko of Russia. Picture: Navesh Chitrakar/Reuters

Victoria Azarenka of Belarus hits a return to Jamie Hampton of the US during their women’s singles match. Picture: Daniel Munoz/Reuters

Fans watch the tennis action at Rod Laver Arena. The stadium, which seats 14 820, has been a tennis venue since 1988. Picture: Navesh Chitrakar/Reuters

Juan Martin del Potro of Argentina covers a camera lens after running through the photographers’ area to return a shot to Jeremy Chardy of France during their men’s singles match. Del Potro lost 6-3, 6-3, 6-7 (3), 3-6, 6-3 in the third round. Picture: Toby Melville/Reuters

Roger Federer of Switzerland hits a return to Jo-Wilfried Tsonga of France during their men’s singles quarterfinal match. The Swiss world no. 2 beat Tsonga to face Andy Murray in the semifinal. Picture: Tim Wimborne/Reuters

Most-tweeted-about player Serena Williams of the US hits a return to compatriot 19-year-old Sloane Stephens during their women’s singles quarterfinal match. Stephens defeated Williams 3-6, 7-5, 6-4 to reach the semifinals but was defeated by Azarenka. Picture: Damir Sagolj/Reuters

Ekaterina Makarova of Russia serves to compatriot Maria Sharapova during their women’s singles quarterfinal. Sharapova went through to the semifinal where she was defeated by Li Na. Picture: Damir Sagolj/Reuters

World no. 1 Novak Djokovic of Serbia signs autographs for fans after defeating Tomas Berdych of the Czech Republic 6-1, 4-6, 6-1 in their men’s singles quarterfinal. He also beat David Ferrer in the semis. Picture: Daniel Munoz/Reuters