Paula Badosa and Madison Keys will be out to prevent a dream Australian Open final when they face Aryna Sabalenka and Iga Swiatek, respectively, in Thursday's semi-finals at Melbourne Park. Sabalenka is on course to become the first woman to complete a "three-peat" since Swiss great Martina Hingis from 1997-90,

Paula Badosa thought she might retire due to a back injury. A year later, she's in to the semifinals against close friend Aryna Sabalenka.

Coco Gauff of the U.S. reacts during her quarterfinal match against Paula Badosa of Spain during their quarterfinal match at the Australian Open tennis championship in Melbourne, Australia, Tuesday, Jan.