By Shrivathsa Sridhar and Ian Ransom MELBOURNE (Reuters) -Defending champion Aryna Sabalenka and Madison Keys made sluggish starts on Thursday but sealed contrasting victories to set up an Australian Open final showdown that will pit two of the game's heavy hitters against each other.

Double defending champion Aryna Sabalenka has reached her third successive Australian Open final, where she will face first-time finalist Madison Keys. Sabalenka will be bidding for her fourth Grand Slam title in the women's decider on Saturday.

American Madison Keys stunned world No. 2 Iga Świątek in an all-time Australian Open classic, coming from a set down to win 5-7, 6-1, 7-6(8) and set up a final showdown against Aryna Sabalenka.