Women's champion Serena Williams, bidding for her 22nd Grand Slam title, will have to overcome No 4 seed Agnieszka Radwanska in the first singles semi-final at the Rod Laver Arena.
The No 1 seed has buried fears about her form and fitness beneath a run of dominating performances. She has not lost a set so far and barely broke a sweat while vanquishing number five seed Maria Sharapova in the quarter-finals.
Poland's Radwanska beat Spain's Carla Suarez Navarro 6-1, 6-3.
Williams is a fan of Radwanska, but their friendship will take a back seat for a few hours on Thursday.
"I know Aga really well. Whoever wins, we both deserve to be in the final. If she wins, I'll be very happy for her. I'm sure she'll feel the same way," Williams said.
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