Sunday's fourth-round slate of women's matches was as good as you could ask for, and the players delivered. Catch up on everything with the scores, the scenes and the stories from the Australian Open.
Naomi Osaka  vs. Garbine Muguruza 
The Score: Osaka wins, 4-6, 6-4, 7-5
The Summary: The Spaniard's brilliance a Melbourne tune-up tournament has carried over into the main event, with her early play against the 2019 champion the best evidence so far. Hitting with pace and precision—a nearly unbeatable combination, considering how much velocity she can generate—Muguruza broke Osaka late in the first set, consolidated with the lead, and took an early break lead in the second.
It only managed to inspire Osaka to raise her own level. From 2-1 down, she won five of the next seven games, with her second break forcing a decider. Whether on serve or return, Osaka found her familiar groove. Would both players find their best when it mattered most?
At times, yes. First, the pendulum swung back Muguruza's way. She broke at 2-2, after an Osaka double fault (in that game, the normally stoic 23-year-old tossed her racquet to the ground), then consolidated. The match appeared to be hers after she a) saved two break points at 3-4, hitting two aces and a running backhand winner to hold; b) earned two match points in the subsequent game.
But just then, the pendulum swung back to Osaka. She saved both match points, then broke when she had to for 5-5, mainly on the strength of booming backhands. In truth, though, all of her strokes were bombing the opposite baseline—and her level got to a point even Muguruza couldn't reach. Osaka won 10 of the final 12 points, broke Muguruza at love, and stunningly turned around a classic fourth-rounder.
The Story: "A backhand miss from Osaka yielded a pair of match points for Muguruza, but the former Melbourne champion found a miraculous final gear from there, breaking Muguruza as she served for the match. Osaka then eliminated her unforced errors entirely through the final four games to race into the quarterfinals."—David Kane (Read the full story here.)
Marketa Vondrousova  vs. Hsieh Su-wei
The Score: Hsieh wins, 6-4, 6-2
The Summary: Like Muguruza, Hsieh served out the first set and immediately broke to open the second. Her momentum never slowed; it only grew in intensity. Vondrousova could get no read on Hsieh's varied arsenal, and the 21-year-old 2019 Roland Garros runner-up is out—while the 35-year-old is into her first Grand Slam singles quarterfinal.
Waiting for her? Naomi Osaka.
The Story: "Though a 2019 Roland Garros finalist, Vondrousva handled Hsieh's tactics with a lack of maturity and experience. The world No. 20’s body language was negative from the very start, looking exasperated at Hsieh’s trickery and later, grimacing in pain. Any long point had her bent over at the waist, though in her defense, she had both upper legs taped."—Nina Pantic (Read the full story here.)
Aryna Sabalenka  vs. Serena Williams 
The Score: Williams wins, 6-4, 2-6, 6-4.
The Summary: After nine games, only two break points had been played—both by Sabalenka—and neither had been converted.
Returning at 5-4, Williams reached 0-30. After recovering to 30-30, a double fault gave Williams her first set point. A heavy second serve, followed by a too-deep return, kept the set alive. But when Serena earned her second set point shortly after, and engaged in a fierce crosscourt rally, Sabalenka wouldn't be the beneficiary of charity.
But instead of building upon the first set—a close, strong-serving contest—the second set effectively reset this fourth-rounder. Williams' serve stats were examples of extremes: She made just 36% of her first serves, yet won 86% of those points. She wasn't as fortunate on her second serve, winning just 5 of 21 points (24% conversion). With those numbers, it was no surprise to see Sabalenka run out the set quickly, and force a decider.
With the rollercoaster nature of play—hitting her own reset button, Williams took a 4-1 lead in the third set—frustration was audible and plentiful amongst these two passionate players.
And as often the case with emotional players, releasing the tension works their advantage. Sabalenka took the next three games with the type of hitting—along with a few timely yells—that's made her one of the hottest players on tour.
But it was only temporary. After Williams stemmed the tide with a hold, Sabalenka played an exceptionally poor service game at 4-5 to permanently lose control of the match. Williams' quest for Grand Slam singles title No. 24 will continue, as Sabalenka continues to search for her first—and, for that matter, her first major quarterfinal.
The Story: "For all the passion she brings to competition, Sabalenka’s emotions often create a rollercoaster effect, when it might be more helpful to stay calm and let her racquet speak most loudly. This could well be a tricky calibration. How best to harness the firepower without dampening it?"—Joel Drucker (Read the full story here.)
Simona Halep  vs. Iga Swiatek 
The Score: Halep wins, 3-6, 6-1, 6-4.
The Summary: "She hoped for a mistake, and this lady is not going to make those mistakes anymore," said Rennae Stubbs on ESPN2.
For years, "She" would have been referring to Swiatek, still just 19 and a relative newcomer to high-pressure matches at the majors; "this lady" would have been Halep, a Grand Slam champion since 2018 and a two-time year-end No. 1 . But with Swiatek's win at Roland Garros last fall, the Pole has entered the elite tier of players on tour, changing the conversation about her practically overnight.
Stubbs was referring to a Swiatek break point late in the first set, which she converted as Halep relied on defensive tennis—losing tennis, against a player as offensively gifted as her confident opponent. With a hold to consolidate, Swiatek had now won 21 consecutive sets at the Slams.
As she's said since her Grand Slam conquest, Swiatek is seeking consistency in her quest to become a No. 1 herself. The rest of the match showed why that's still a concern for Swiatek, whose form tumbled, without warning. Halep took the first three games of the second set, and four games later, Swiatek's remarkable run at the majors had come to an end. That was a streak of sets, but she was also losing her grip on the match.
Halep continued to apply pressure, notching an early break in the third set. With the match getting away from her, Swiatek got on the board with a tough hold for 1-2—and broke back for 2-2. It was a temporary reprieve. Swiatek made 42 unforced errors, compared to Halep's 17. Part of the reason for the disparity? First-serve succes. The Romanian won 77 percent of her first-serve points, compared to Swiatek's 59.