No. 2 seed Karolina Pliskova and No. 5 Elina Svitolina stumbled out of the Australian Open on Saturday after a pair of third-round upsets in Melbourne.

No. 30 seed Anastasia Pavlyuchenkova of Russia outlasted Pliskova 7-6 (4), 7-6 (3) for her first win against the Czech in seven tries. The match lasted two hours, 25 minutes.

"I am really happy, it was a lot of fun," said Pavlyuchenkova afterward. "I really enjoyed it and even had goosebumps after some points. To get a win and beat Karolina for the first time was amazing."

Pavlyuchenkova has played some of her best tennis in Melbourne, as she reaches the second week for the third time in four years. She's twice reached the quarterfinals in the event and lost in the final eight last year.

Fending off Pliskova's serve was crucial to Pavlyuchenkova's success, as the Russian forced her into a marathon 30-point effort in her opening service game before jumping out to a 4-1 lead.

"My goal was to return well today, she is the ace queen on tour," said Pavlyuchenkova. "I thought that if I took at least one or two games on her serve, it would be amazing and I also held my serve which helps. It was a good match for me today."

Next up for Pavlyuchenkova is No. 17 Angelique Kerber of Germany, who won here in 2016.

Kerber advanced after holding off Italy's Camila Giorgi 6-2, 6-7 (4), 6-3. It was the fifth time in five tries Kerber has beaten Giorgi, with the last four coming in Australia.

Svitolina's upset was much more one-sided, with Spain's Garbine Muguruza breezing past the Ukrainian 6-1, 6-2 in a match that lasted just over an hour.

"I was very concentrated and focused on what I had to do. Everything went pretty quickly my way, so I'll take it," said Muguruza afterward.

"We always have good matches, so I was really looking forward to playing her."

Muguruza is now 5-6 in her career against Svitolina. She next faces No. 9 Kiki Bertens of the Netherlands, who advanced with a 6-2, 7-6 (3) win over Kazakhstan's Zarina Diyas.

In other third-round matches, No. 4 seed Simona Halep of Romania beat Kazakh Yulia Putintseva 6-1, 6-4 and No. 16 Elise Mertens of Belgium held off CiCi Bellis of the U.S. 6-1, 6-7 (5), 6-0. Halep and Mertens will meet in the next round.

No. 6 seed Belinda Bencic of Sweden, however, won't be advancing after falling to No. 28 Anett Kontaveit of Estonia, 6-0, 6-1.

Kontaveit will face Iga Swiatek of Poland, who eliminated No. 19 seed Donna Vekic of Croatia 7-5, 6-3.