Melbourne - Three-time Grand Slam winner Angelique Kerber survived a scare from 102-ranked Italian Camila Giorgi to reach the Australian Open last 16 on Saturday.
The German 17th seed fought through 6-2, 6-7 (4/7), 6-3 and faces second seed Karolina Pliskova of the Czech Republic or Russia's Anastasia Pavlyuchenkova.
The 32-year-old Kerber won her maiden Grand Slam at the Australian Open in 2016 and claimed the US Open title later the same year. She triumphed at Wimbledon in 2018.
"It was a really tough battle, I started really well but she came back really strong," said Kerber.
"It's still a long way to go, I need to keep fighting.
"I'm enjoying playing here and being here," she told the crowd at Margaret Court Arena.
The 28-year-old Giorgi refused to go quietly in a sunny and hot Melbourne.
Former world number one Kerber saved three break points to grimly hold serve in the third game of the deciding set and then broke the Italian for a 3-1 lead.
But Giorgi wrestled the break back, leaving a disgruntled Kerber muttering to herself on her chair at the changeover.
Whatever she said to herself, it worked, Kerber breaking again for 5-3 before serving out a tough contest in two hours and eight minutes.