Defending champion Victoria Azarenka overcame injury problems to end Sloane Stephens' Australian Open run and set up a final with China's Li Na.
Azarenka left the court for almost 10 minutes to have treatment for what appeared to be stress after the American had saved five match points
But the Belarusian, who hurt her left ankle earlier in the set, broke in the next game to win 6-1 6-4.
Li Na crushed Maria Sharapova with a magnificent display to power into her second Australian Open final. Sharapova had broken a tournament record in conceding just nine games in reaching the last four but she was overwhelmed by the Chinese whose heavy-hitting, high-risk game reaped maximum reward.
In the face of blazing winners from all angles, second seed Sharapova had no answer as Li romped to a 6-2, 6-2 win.
Defending champion Novak Djokovic thrashed David Ferrer to reach the Australian Open final and stay on course for a hat-trick of Melbourne titles.
Djokovic had too much pace on the ground and off his strings for the Spaniard, winning 6-2 6-2 6-1 in one hour and 29 minutes.
It was in marked contrast to last year's semi-final, when the Serbian had needed nearly five hours to see off Andy Murray.
Djokovic went on to win his third Australian title in 2012, and this year is trying to become the first man since the Open era began in 1968 to win it three times in a row.