Maria Sharapova set up a WTA Championship final showdown against Serena Williams with a convincing 6-4 6-2 victory against Victoria Azarenka.
The Belarusian went into the clash leading 4-1 in their head-to-head meetings, but the French Open champion showed a fierce determination from the off, using bold tactics to frustrate her opponent.
Azarenka, who had already made sure of the year-end world number one ranking with victory over Li Na on Friday, was denied room to dominate as Sharapova clobbered 30 clean winners on a slow surface.
After the Russian won a close opening set, the decisive break in the second came during the important sixth game, which lasted 15 minutes.
A fired-up Sharapova, who was serving, broke Azarenka's resistance to take a 5-1 lead with a raking cross court drive before avenging important Grand Slam defeats in Melbourne and New York on her next service game.
Sharapova will now fancy her chances of regaining a WTA Championships title she last won in her breakthrough year back in 2004.
"I have lost to Victoria a few times so I was happy to get the chance to play against her," said Sharapova.
"Against the world number one, you have to run down every ball. She's number one for a reason so I had to be ready for every shot.
"It will be a difficult match against Serena. She's been on fire, she's the one to beat."