Danielle Collins has been eliminated from the Australian Open 12 months after she went down to Ash Barty in the women's final.
Collins had struggled through to the last 32 following gritty wins in the opening two rounds, but she could not get the better of Wimbledon champion Elena Rybakina on Friday.
Kazakhstan's Rybakina triumphed 6-2, 5-7, 6-2 over the 13th seed.
"I'm super happy," Rybakina said in her on-court interview.
"It was a really difficult match. Danielle played really well.
"I started really well and Danielle raised her level in the second set. It was really close."
Rybakina, seeded 22 at Melbourne Park, will face world number one Iga Świątek in the last 16.
Świątek raced through her third-round match against Spanish qualifier Cristina Bucșa, winning 6-0, 6-1 in 55 minutes, while seventh seed Coco Gauff defeated fellow American Bernarda Pera 6-3, 6-2.
Gauff will next play Latvian 17th seed Jelena Ostapenko, who won 6-3, 6-0 over Ukrainian Kateryna Baindl.
World number three Jessica Pegula also advanced, landing her seventh consecutive straight-sets win to earn a tantalising clash with Czech Barbora Krejčíková.
Pegula barely raised a sweat in her 6-0, 6-2 thrashing of Ukrainian Marta Kostyuk, needing just an hour and five minutes to seal a fourth-round berth.
The in-form American will next face the resurgent Krejčíková, who easily beat Kostyuk's countrywoman Anhelina Kalinina 6-2, 6-3.
Krejčíková is the 20th seed at Melbourne Park this year after an elbow injury and dipping form in majors hurt her ranking, but she regained form late last year and shapes as a dangerous prospect.
Pegula is suitably wary of Krejčíková, who has won all four doubles majors, been ranked as high as number two in the world in singles, and reached the quarterfinals at the Open last year.
"Obviously I've watched her quite a bit," Pegula said.
"She's had a great couple of years. Obviously last year she was a little bit hurt. It seems like she's finding her confidence again."
Krejčíková, the 2021 French Open singles champion, is yet to drop a set and has only lost 14 games across her first three matches.
"Everything is improving. I think with every single match I'm getting better and better," she said.
"I'm really happy with the way I'm winning so far."
AAP/ABC
