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Australian Open: Victoria Azarenka falls to Agnieszka Radwanska
January 22, 2014 -- Updated 1322 GMT (2122 HKT)
World No. 2 Victoria Azarenka had taken the women's title at Melbourne Park in each of the past two years.
- Defending champion Victoria Azarenka beaten by Agnieszka Radwanska at the Australian Open
- World No. 2 Azarenka has taken the title at Melbourne Park in each of the past two years
- Fifth seed Radwanska will play Slovakia's Dominika Cibulkova in the semifinals
- Cibulkova beat Romania's Simona Halep to reach the last four
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(CNN) -- The Australian Open is known as the "Happy Slam." The players are usually re-energized after the off-season and gush over the way the tournament is organized.
But for the fourth day in a row in Melbourne, a multiple grand slam winner left the tournament without a smile on their face.
Following Serena Williams, Maria Sharapova and Novak Djokovic, two-time women's defending champion Victoria Azarenka became the latest big name bundled out when the Belorussian fell to Agnieszka Radwanska on Wednesday.
Yes, the upsets keep coming.
Eugenie Bouchard scored a shock victory over 14th seed Ana Ivanovic to reach the semifinals of her first Australian Open. The Canadian came back from one-set down 5-7 7-5 6-2.
Bouchard the Belieber
Li Na faced a battle to stay cool and to stay in the Australian Open against Lucie Safarova.
Australian Open hots up
Radwanska not only defeated Azarenka in the quarterfinals to snap a seven-match losing streak against the world No. 2 but she didn't drop a game in the third set of the 6-1 5-7 6-0 victory.
When Azarenka misfired to seal her fate on match point, the crowd at Rod Laver Arena roared its approval.
With Djokovic departing Tuesday at the hands of Stanislas Wawrinka, it marked the first time in the Open Era both the men's and women's defending champions in Australia were eliminated at the quarterfinal stage.
"I think about today's match, what I did, what I could do better," Azarenka told reporters. "But other players, different vibe, whatever, I don't really care about that."
World No. 2 Novak Djokovic has won the season's first grand slam in each of the past three years. But not this year..
Wawrinka ends Djokovic's Australian Open reign
Read: Bouchard the "Belieber" reaches semifinals
Radwanska meets Dominika Cibulkova in the semifinals Thursday after the diminutive Slovak -- who sent Sharapova packing -- cruised past maiden grand slam quarterfinalist Simona Halep 6-3 6-0.
"This is for sure one of the greatest matches at the slam, especially here," Radwanska told reporters. "(Azarenka) is playing great tennis here.
"Especially the third set was unbelievable. I really cannot complain about anything."
Li Na, the only grand slam champion in the women's semifinals and twice the Australian Open runner-up, battles Canadian upstart Eugenie Bouchard in the other semifinal.
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