Federer sends off Murray, next up NadalVictoria Azarenka of Belarus speaks during a press conference after her quarterfinal loss to Agnieszka Radwanska of Poland at the Australian Open tennis championship in Melbourne, Australia, Wednesday, Jan. 22, 2014. (AP Photo/Shuji Kajiyama)
MELBOURNE, Australia (AP) -- Even in a Grand Slam as unpredictable as this year's Australian Open, the names in the women's semifinals may still prompt head-scratching among casual followers of tennis.
With the three biggest stars of the women's game falling one by one - top-seeded Serena Williams, followed by Maria Sharapova and two-time Australian Open champion Victoria Azarenka - the door has opened for a first-time winner at Melbourne Park.
Only fourth-seeded Li Na has won a Grand Slam before - the 2011 French Open.
Fifth-seeded Agnieszka Radwanska of Poland was the 2012 Wimbledon finalist, but had never been beyond the quarters in Melbourne until she chipped, lobbed and sliced Azarenka off the court in a remarkable display of shot-making on Wednesday.
Dominika Cibulkova, a diminutive Slovakian who dispatched Sharapova in the fourth round, has made just one Grand Slam semifinal before, while 19-year-old Eugenie Bouchard is a only playing her fourth major - she didn't even make it out of qualifying at last year's Australian Open.
With such a golden opportunity for one of the four to now break through and capture a major, the deciding factor in the semifinals may be who can best handle the pressure.
''Of course, a couple seeded (players) are out. Doesn't mean it's going to be easier and you have a title right away,'' Radwanska said. ''It's a bit more pressure. This is the semifinal of a Grand Slam.''
Radwanska should know. The draw opened up similarly at Wimbledon last year when Williams and Sharapova were upset early and Azarenka pulled out with an injury, leaving the Polish player as the highest remaining seed and the favorite to capture her first major.
Radwanska, however, crumpled in the semifinals against Sabine Lisicki, blowing a 3-0 lead in the third set. She said it's natural to feel nervous in these situations.
''I think in the beginning of the match it's always a little bit tough, especially it's the first semifinal,'' she said. ''But hopefully after few games I'm going to be myself and play my best tennis.''
Radwanska faces Cibulkova in the semis - a player she's beaten four times in five matches, including a 6-0, 6-0 drubbing in the Sydney International final last year.
Cibulkova knows she doesn't have a great record against Radwanska, but she takes inspiration from Stanislas Wawrinka's upset of four-time men's champion Novak Djokovic in the quarterfinals after 14 consecutive losses to the Serb.
''You just want to prove it to yourself that you can do it, and that's what (Wawrinka) did,'' Cibulkova said.
Li, a two-time finalist at the Australian Open, has the most experience of any of the semifinalists playing in the latter stages of slams, but she's also been susceptible to buckling under pressure.
Li was up a set in the finals here against Kim Clijsters in 2011 and Azarenka in 2013, only to falter both times. She also nervously wasted four match points in a fourth-round loss to Clijsters in 2012, breaking down in tears afterward.
The Chinese star was almost out of this year's tournament, as well, saving a match point against Lucie Safarova in the third round. Since then, however, she's appeared more focused on court, dropping just six games in her last two matches.
The wild card is Bouchard. Li, who will be 32 next month, is 12 years older than the Canadian and has won their only previous meeting, but Bouchard is a rising talent with nothing to lose. She likes her chances in a tournament as topsy-turvy as this one.
''I think some players can still lose on any given day and it still makes it extremely interesting,'' she said. ''I'm feeling confident and just excited to play.''