Long ago, in a distant lifetime, Aryna Sabalenka was a perfectionist.

“I think I have been like that when I was young,” Sabalenka said after winning her third-round match. “Right now, I’m not trying to be perfect. I’m trying to do my job as good as I can.”

Which, in the case of her 6-0, 6-0 victory over No. 28 seed Lesia Tsurenko, was, well, just about perfect.

Australian Open: Scores | Draws | Order of play

“I’m just trying to keep it simple,” Sabalenka said, “because as soon as you start trying to make it perfect, everything goes wrong.”

Bringing us to Sunday’s intriguing fourth-round match against Amanda Anisimova. Most metrics would suggest it’s a mismatch.

Sabalenka, who is featured on Season 2 of Netflix's "Break Point," is ranked No.2 among Hologic WTA Tour players, while Anisimova is a hopelessly distant No.442. Sabalenka is the Australian Open’s defending champion and Anisimova has never been past the fourth round. As Sabalenka was blazing through the 2023 season -- at one point, rising to No.1 --  Anisimova took an extended break, tending to her mental health.

Their Sunday meeting is one of four absorbing Round of 16 matches from the bottom half of the draw. This statistic suggests it could be closer than we think.

Anisimova, a 22-year-old American, has beaten Sabalenka four of the five times they’ve played.

'I know my dad would be proud of me': Sabalenka on becoming No.1

“I’m going to be getting a lot of attention on social media, I guess, being in the second week of a Slam,” Anisimova told reporters. “But that’s never really bothered me. I don’t really go on my phone all that much. I just talked to my friends and family and try and stay away from all the other stuff.”

Both players have produced exceptionally clean runs.

When she lost badly to Elena Rybakina a few weeks ago in the Brisbane final, Sabalenka might now feel like the one to beat.

After scorching a pair of teenage qualifiers, Sabalenka threw in that shutout against Tsurenko, the first of her career. She now has three 6-0 sets in the first three rounds, two more than she had in six previous main-draw appearances. Sabalenka has dropped a scant six games in six sets -- you can do the math. She’s been on court for less than three hours.

Sabalenka has won 10 consecutive matches in Melbourne, the most since Serena Williams from 2017-19. She’s also won the most hard-court matches in women’s Grand Slams (32) in the past four years.

Anisimova, meanwhile, has been efficient, winning each of her sets against No.13 seed Liudmila Samsonova, Nadia Podoroska and Paula Badosa. Anisimova was down two breaks to Badosa in the first set and rallied to win 7-5, 6-4. The only extenuating circumstance was a medical timeout for what she later said were stomach cramps.

Anisimova has won only two career titles -- 11 fewer than Sabalenka -- but reached the semifinals at Roland Garros at the age of 17 and the quarters at Wimbledon two years ago.

About that head-to-head: After Anisimova won the first four matches, Sabalenka broke through with a three-set victory in the 2022 Rome quarterfinals.

“I’m happy that she’s back on tour,” Sabalenka said of Anisimova. “We had a lot of great matches against each other, always tough battles. I’m just trying to prepare myself as good as I can, and so make sure I bring my best level and I compete in the high level.”

Which, so far, has been perfectly good enough.

More to watch on Day 8

Andreeva fever 

This is eerily reminiscent of Coco Gauff’s 2019 run at Wimbledon as a 15-year-old when she stunned Venus Williams on the way to the fourth round.

Mirra Andreeva upset No.6 seed Ons Jabeur -- 6-0, 6-2 in the second round -- and then completely outdid herself in the third round.

Down 5-1 in the third set to Diane Parry, the 16-year-old Andreeva saved a match point and went on to win a tiebreak to set up Sunday’s match with No.9 seed Barbora Krejcikova.

“I just tried to win at least one more game to not go 6-1, 1-6, 6-1,” Andreeva said of that monstrous hole. “Then 5-2, she has match point. I’m going to the net. I’m thinking, `Am I crazy? I'm going to the net on match point?’ But then she missed a ball. 

“I feel like when you're coming back from this score, it’s kind of easy on a mental side for you. It’s easier than for your opponent, for sure, because you’re on the run, you’re having all the adrenaline. That’s what I had today.”

ESPN analyst Mary Joe Fernandez praised her tennis IQ, saying she reminded her of three-time Australian Open champion Martina Hingis. Andy Murray extolled her mental toughness on social media.

Next up for Andreeva is No.9 seed Barbora Krejcikova, who defeated Storm Hunter 4-6, 7-5, 6-3. While two of her matches have gone the distance, Krejcikova has displayed her characteristic composure. Her 12 wins Down Under -- she was a quarterfinalist here in 2022 -- are the most in any Slam for the 2021 Roland Garros champion.

Experience may not be a factor, though, for Andreeva won both their previous matches, last year at Wimbledon and Beijing.

Another grand opening

No.4 Coco Gauff wasn’t far behind Sabalenka’s masterful third-round performance, defeating fellow American Alycia Parks 6-0, 6-2 in 61 minutes.

That gave the 19-year-old a 10th consecutive Grand Slam match win, something Iga Swiatek did between 2020 Roland Garros and the 2021 Australian Open when the worldwide pandemic rearranged the major schedule.

Gauff won the title at the ASB Classic in Auckland and, like Swiatek, has started the season undefeated. It happened last year, too, but Gauff fell in the fourth round here to Jelena Ostapenko.

Gauff hopes to go one better against Magdalena Frech, who defeated qualifier Anastasia Zakharova 4-6, 7-5, 6-4. Frech, a 26-year-old from Poland, is ranked No.69. This is a first-time match.

Out of nowhere

Maria Timofeeva arrived in Melbourne coming off two tough losses -- in a WTA 125 in Canberra and an ITF $100,00 event in Dubai. Timofeeva was beaten by two players whose rankings were well past No.150.

How, then, to explain what’s happened here?

In women's tennis it’s not a lot about the game, it’s more about mental part,” Timofeeva said. “I always felt that I have something in my game that I can pursue. So I think now is just everything coming up together. I’m having one of the best weeks of my life so far.”

The 20-year-old won three qualifying matches, then three more in the main draw. Her opponents: Alize Cornet, Caroline Wozniacki and No.10 seed Beatriz Haddad Maia -- 7-6 (7), 6-3. She’s the first qualifier to reach the fourth round at the Australian Open since Denisa Allertova in 2018.

Kostyuk's pursuit for success Down Under amid her country's ongoing war

Next up: Marta Kostyuk, 21, who has navigated her way nicely, defeating No.25 Elise Mertens in the second round, and Elina Avanesyan in the third. 

Kostyuk and Timofeeva have never played. 

Day 8 schedule of play

Rod Laver Arena

Day session starts at noon
 
Magdalena Frech vs. (4) Coco Gauff
 
Not before 1:30 p.m. 
 
(20) Adrian Mannarino vs. (1) Novak Djokovic
 
Night session starts at 7 p.m. 
 
(10) Alex de Minaur vs. (5) Andrey Rublev
 
Aldila Sutjiadi & Michael Venus vs. Olivia Gadecki & Marc Polmans 
 

Margaret Court Arena

Day session starts at 12 p.m.
 
TBA
 
Not before 1 p.m. 
 
Amanda Anisimova vs. (2) Aryna Sabalenka
 
Not before 4 p.m. 
 
(4) Jannik Sinner vs. (14) Karen Khachanov
 
Gabriela Dabrowski & Erin Routliffe vs. Veronika Kudermetova & Anastasia Pavlyuchenkova 

John Cain Arena

Day session starts at 11 a.m. 
 
TBA
 
Not before 1:30 p.m
 
(12) Taylor Fritz vs. (7) Stefanos Tsitsipas
 
Mirra Andreeva vs. (9) Barbora Krejcikova