Gauff claimed a more straightforward victory, moving past 30th seed Leylah Fernandez with a 6-4 6-2 win in 76 minutes.
The world number three, who reached the semi-finals in Melbourne last year, improved as the match went, stamping out unforced errors as she clinched three successive breaks at the start of the second set.
Asked what keeps her grounded during Grand Slams, 20-year-old Gauff replied: “The people that I meet every single day make me realise that tennis feels such high stakes but it’s really not.
“I’m so lucky to be able to do what I do, get paid well by doing it and be able to use my platform to give back to others. I’m very grateful.”
But American seventh seed Jessica Pegula became the latest top-10 player to fall as she went down 7-6 (7-3) 6-1 to Serbia’s Olga Danilovic.
The 23-year-old was cheered on by compatriot Novak Djokovic on Rod Laver Arena following his third-round victory and she dominated the second set to set up a fourth-round tie against Spanish 11th seed Paula Badosa.
Meanwhile, 18th seed Donna Vekic beat Diana Shnaider 7-6 (7-4) 6-7 (3-7) 7-5 and will face 27th seed Anastasia Pavlyuchenkova in the fourth round.