Ashleigh Barty has staged a stirring fightback to storm into her maiden grand slam quarter-final with a drama-charged Australian Open victory over Maria Sharapova.

Barty overcame a nervy, error-riddled first set to defeat the five-times major winner and former world No.1 4-6 6-1 6-4 in a rousing fourth-round performance on Sunday.

Australia’s first women’s quarter-finalist at Melbourne Park since Jelena Dokic a decade ago, 22-year-old Barty will play Czech world No.6 Petra Kvitova on Tuesday for a spot in the semi-finals.