Sharapova broke Kvitova’s serve in the last game to finish off a 6-2, 3-6, 6-4 Thursday, and third-seeded Azarenka beat defending champion Kim Clijsters 6-4, 1-6, 6-3 to set up a Saturday night final at Rod Laver Arena that also will decide the No. 1 ranking.

Sharapova lost to second-ranked Kvitova in the Wimbledon final last year, her first major final since returning from an injury layoff following a shoulder operation in 2008. She has won three majors, but none since the Australian four years ago.

“In the third set, I felt she always had the advantage because I was always down on my serve,” said Sharapova, who served five double-faults in the third set and 10 in the match. “I just told myself ‘You just gotta go for it, don’t let her finish off the points like she likes to.”’

Azarenka won the first semifinal after twice recovering from periods when a resurgent Clijsters seemed to have the upper hand, to secure victory in only her second appearance in a major semifinal.

“I felt like my hand is about 200 kilograms and my body is about 1,000 and everything is shaking, but that feeling when you finally win is such a relief. My God I cannot believe it’s over. I just want to cry,” Azarenka said as she choked back tears, then buried her face in a towel.

“It was just trying to stay in the moment. Kim really took over the second set and I felt there was nothing I could do. I just tried to regroup.”

Clijsters is popular in Australia, where she’s widely known as “Aussie Kim.” She had most of the backing from the crowd on the national holiday in what is likely to be her last Australian Open.

Azarenka held her nerve despite the crowd and the fact she was up against a proven big-match player. Clijsters has won four majors and has defended a Grand Slam title—winning the U.S. Open in 2009 and ’10. To reach the semifinals, the Belgian saved four match points despite a sprained ankle to beat French Open champion Li Na in the fourth round and then beat top-ranked Caroline Wozniacki in the quarterfinals.

“I guess before you all thought I was a mental case,” Azarenka said in a courtside interview. “I was just young and emotional. I’m really glad the way I fight, that’s the most thing I’m really proud of. I fight for every ball.”

Clijsters credited Azarenka with increasing maturity.

“The match was very close. There were a few deciding moments where I think I maybe had a little bit of an advantage, in the third set, especially that first game where I had break point,” Clijsters said. “But she definitely played really well. So she deserved to win at the end.”

Wozniacki will vacate top spot in next week’s rankings after her quarterfinal loss, leaving either No. 3 Azarenka and No. 4 Sharapova to move to the top.

The top men’s ranking won’t be at issue Thursday night. Novak Djokovic—who plays Andy Murray in another semifinal on Friday—has that locked up regardless of the Australian Open results.

But the Nadal-Federer semifinal will mark the first time since the French Open in 2005 that the pair have met at the next-to-last stage of any Grand Slam. Federer and Nadal were Nos. 1 and 2 for most of five years from 2005 to 2010, meaning they were on opposite sides of the draw and could not meet until the final.

That changed at this tournament when No. 2 Nadal and No. 3 Federer both ended up in the bottom half of the draw. Five matches later, the players with 26 Grand Slam singles titles between them—Federer 16, Nadal 10—will meet.

Nadal has won 17 of their 26 head-to-head matches overall, including a 7-2 lead in Grand Slam matches. Federer won the last meeting, a 60-minute 6-3, 6-0 victory at the season-ending championship in November.

“We have been on opposite sides of the draw many times,” Federer said. “I guess it’s a nice change-up. OK, it doesn’t allow a rematch for the Australian Open final here, you know, but I think it’s good for tennis that it changes up a bit.”

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