Stanislas Warwinka edged Tomas Berdych in the tightest of duels to reach his first grand slam final at the 36th attempt on Thursday and set up a possible all-Swiss Australian Open title showdown against Roger Federer.

Federer will have to get past world number one Rafa Nadal in the second semi-final on Friday first, but 28-year-old Wawrinka did his part by the narrowest of margins with a 6-3 6-7(1) 7-6(3) 7-6(4) victory over the tall Czech.

The earlier women's semi-finals were one-sided affairs with China's Li Na beating teenager Genie Bouchard 6-2 6-4 to get to her third Melbourne final and diminutive dynamo Dominika Cibulkova downing Agnieszka Radwanska 6-1 6-2 to reach her first.

There was nothing uneven about the battle between the seventh seed Berdych and eighth seed Wawrinka that followed on Rod Laver Arena in which three of the four sets were decided by tiebreaks.

While Wawrinka's victory over defending champion Novak Djokovic in the quarter-finals was all about guts and shotmaking, the arm-wrestle with Berdych was a study in big serving and heavy hitting.

Wawrinka grabbed the only break of serve in the contest to take the first set and exactly three hours later he clinched the fourth-set tiebreak on his second match point, a thumping unreturnable serve providing a fitting climax.

"It's amazing. I didn't expect to make a grand slam final in my career," Wawrinka said before turning his mind to the possibility of facing Federer.

"To play a Swiss final will be amazing, first for Switzerland, for the country. He is the best player ever. For me it's my first final. To imagine to play against Roger would be amazing."

The bald statistics showed the Swiss won 143 points to Berdych's 142, the Czech edged the ace count 21-18 and had more winners (60-57), while there were 49 unforced errors apiece.

"It was one point and one break, that's it," said a crestfallen Berdych, who earned just one break point at 4-4 in the third set but failed to convert it.

"If I could tell what was the difference (between us) then I would be nearly a genius.

"We both play great. We play a good match. Stan was the one that just took it, and that's it."

BULLET DODGED

With top three seeds - Serena Williams, Victoria Azarenka and Maria Sharapova - all victims of upsets, Li knows she will rarely have a better chance of adding another grand slam title to her 2011 French Open crown.

The 31-year-old, who dodged a bullet when she faced match point against Lucie Safarova in the third round, set off at a blistering pace and won 20 of the first 23 points to take a 5-0 lead.

It could not last and the 19-year-old Canadian broke and held serve for 5-2 before fourth seed Li upped her game again and wrapped up the first set with a forehand volley.

The second set was a closer affair with Bouchard grabbing an early break but Li ramped up the power on her groundstrokes and added another 22 winners to the 13 she smashed in the opening stanza to seal victory.

"I think the beginning of the match I played very well," said Li. "The second set was a little bit tighter because I was feeling that I already had one foot in the final.

"I think is the third time (in the final), so I'm pretty close to the trophy."

Bouchard, the world number 31, again reiterated that she had not been surprised to reach her first grand slam semi-final.

"I wouldn't say I exceeded my expectations, but I'm happy with how I did," the former Wimbledon junior champion said. "I've slowly been making my way up. I don't want to stop here.

"I feel like I belong in the top levels of the game."

Cibulkova lay down on the court and kicked her legs in the air in delight after the quickfire victory over fifth seed Radwanska that made her the first Slovakian woman to reach a grand slam final.

The 24-year-old has been on fire at Melbourne Park this year, belying her lowly seeding by upsetting Sharapova and doling out a string of thrashings as she made her way to the last four.

The 20th seed scuttled around the Rod Laver Arena feasting on the lethargic Pole's second serve and blasting winners from both sides.

She grabbed three breaks of serve to take the first set with a crunching backhand winner and was celebrating her victory just 33 minutes later when Radwanska netted.

"It's like a dream. It's something so unbelievable," she said. "I was 100 percent ready for it and I was just doing what I had to do. That's why I won."

Radwanska was as bad on Thursday as she had been brilliant in beating double defending champion Azarenka on Wednesday and blamed her quarter-final effort for her lackluster display.

"I think I feel like in slow motion today. I had a couple tough matches, especially yesterday. I think I was not fresh enough," she said.

"I was late for pretty much every ball. I could really feel that it was not really my day."