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's retooled forehand and serve abandoned her in the worst way and at the worst time at the Australian Open. The unforced errors just kept accumulating Tuesday, and so did the double-faults and break points,

In her last Grand Slam quarterfinal, the Spaniard imploded in New York. She is taking the lessons into her match with Gauff in Melbourne.