Japanese US Open champion Naomi Osaka ground her way into the women's singles Australian Open quarter-final with sixth seed Elina Svitolina Monday ahead of Serena Williams facing her biggest tennis test since giving birth.
But prodigious Alexander Zverev went into meltdown and crashed out, losing to Milos Raonic in their Round of 16 clash at Rod Laver Arena, Melbourne.
As the second week of the opening Grand Slam of the year got underway, fourth seed Osaka was still standing after emerging from an error-strewn first set against crafty Latvian Anastasija Sevastova to win 4-6, 6-3, 6-4.
The victory left the bubbly 21-year-old with a last-eight clash against ambitious Ukrainian Svitolina, who battled past American Madison Keys 6-2, 1-6, 6-1.
It will be a new experience for whoever wins that showdown, with neither of them going beyond the quarter-finals at Melbourne Park before.
This contrasts with the massively experienced Serena Williams who has made the last eight or better 11 times on her way to seven Australian Open crowns.
The 37-year-old 23-time Grand Slam winner has a blockbuster last-16 evening clash against world number one Simona Halep on Rod Laver Arena, while Novak Djokovic meets fast-rising Daniil Medvedev.
Osaka beat Williams to clinch the title at Flushing Meadows last year. It propelled her to stardom, but she has been far from convincing at her first major since.
"I didn't give up, she was playing really well and I wasn't really sure what to do at a certain point, but I just tried to stick in there," she said.
"I was watching all these kids winning. Last night (Stefanos) Tsitsipas beat (Roger) Federer and I was like whoa, and I decided I wanted to do well too."
Svitolina needed to dig deep to overcome 17th seeded Keys, a US Open finalist in 2017.
The turning point was a marathon 16-minute game early in the deciding set that went to deuce 11 times as Keys chased a decisive break.
But the American's resolve crumbled when Svitolina held off five break points then gained an advantage in the next game.
"I had to put my level up, I'm glad I handled the pressure," said Svitolina, who scored her biggest career win at the WTA Finals in Singapore last October.
"It was very hard because the sun was burning my eyes when I was tossing the ball, so I was very happy to win."
Svitolina was a quarter-finalist at Melbourne Park last year and has set her sights high after her breakthrough in Singapore, targeting a Grand Slam win and world number one.
In the men's section, Zverev erupted in frustration and fury during the second set of a 6-1, 6-1, 7-6 (7/5) drubbing by the Canadian 16th seed, hammering his racquet into the ground eight times to leave it a mangled mess.
"I just tried to stay composed, "said Raonic.
"It worked extremely well for me today.
"I played incredibly good, did a lot of things extremely well."
Zverev was tipped as a future Grand Slam champion after a breakthrough 2018 that saw him win the ATP Tour Finals, beating Novak Djokovic and Roger Federer in the process.
Instead, it was a familiar tale of woe as his much vaunted-talent deserted him again before he could reach the sharp end of a major.
The 21-year-old's miserable record in Slams was extended to just one quarter-final, at the French Open last year, in 15 appearances.
All seemed well when the world number four broke former world number three Raonic's formidable serve in the opening game of the match.
"I was glad I turned around that start quickly," said Raonic.
"I gave myself a lot of curse words after the first game." But he then lost the next nine in an error-strewn display.
Zverev committed eight double faults and 16 unforced errors against only eight winners as the first two sets evaporated in 63 minutes.
When he dropped his serve to go 4-1 behind in the second set his seething anger was taken out on his unfortunate racquet, earning a code violation from umpire Carlos Ramos.
Zverev left the court for a bathroom break at the end of the set to let off steam and was at least competitive when he returned.
He stopped the flood of mistakes in the third set and took it to a tiebreak, saving two match points along the way.
But it was too little, too late as Zverev's abject record in Slams continued.
Instead Raonic, who lost to Andy Murray in the last four in Melbourne in 2016, moves on to face Borna Coric or Lucas Pouille in the quarter-finals.
(With AFP inputs)
