Six-time major champion Iga Swiatek endured a roller-coaster ride before sealing her place in the Australian Open last 16 on Saturday.
The Polish second seed, who is chasing a maiden Melbourne title, wobbled before beating 31st Russian seed Anna Kalinskaya 6-1, 1-6, 6-1.
Swiatek faces qualifier Maddison Inglis next after Naomi Osaka pulled out of her third-round match against the Australian because of injury.
