Gauff wins all-American clash to reach Australian Open last 16
The 18-year-old won 6-3, 6-2 on Rod Laver Arena to set up a last-16 clash against the 2017 French Open champion Jelena Ostapenko of Latvia.
A maiden Grand Slam title for seventh seed Gauff would make her the youngest Melbourne champion since a 16-year-old Martina Hingis 26 years ago.
Gauff headed into the first major of the year on a high after winning her third WTA title at the Auckland Classic earlier this month.
She admitted she "got lucky" in her tight second-round victory over Emma Raducanu in a battle of tennis prodigies.
But Gauff let her racket do the talking in her first meeting with power-hitter Pera, relentlessly soaking up some late pressure from the world number 41 when serving for the match at 5-2.
"She was hitting the ball really hard," said Gauff, who this week became the first woman to register 100 tour-level wins before her 19th birthday since Caroline Wozniacki in 2009.
"So I was trying to hang in there and take the ground when I could.
"Last season she had a really long match streak so I knew she would be a tough player to beat, so I'm glad to be through to the second week."
Gauff is one of two teenagers left in the women's draw. The other is 17-year-old Linda Fruhvirtova, who plays Marketa Vondrousova in an all-Czech third-round clash on Saturday.
