Alexander Zverev served up a huge shock at the Australian Open by stunning second seed Carlos Alcaraz to make the semi-finals after third seed Daniil Medvedev fought hard to avoid an upset at the hands of Hubert Hurkacz.
Ukrainian qualifier Dayana Yastremska and Chinese 12th seed Zheng Qinwen earlier progressed to the last four of a Grand Slam for the first time after contrasting victories from a wide-open section of the women's draw.
Zverev was near-flawless on his delivery early in the clash on Rod Laver Arena and the sixth seed took advantage of mistakes from the racket of Alcaraz to lay the foundation for a 6-1 6-3 6-7(2) 6-4 victory.
Battling fatigue and an issue with his toes, German Zverev held firm in the face of relentless pressure to secure the win and set up a semi-final showdown with Medvedev, who has won 11 of their 18 previous meetings.
"I'm extremely happy to be back where I am and winning these kinds of matches and giving myself the chance again," Zverev said.
"Because last year, for the first part of the season, or actually throughout the year, I wasn't a slam contender.
"I wasn't a contender to win tournaments like that. If I am now, I'm very happy about that."
Third seed Medvedev, who lost back-to-back Melbourne Park finals in 2021 and 2022, pounced on the few chances offered up by Pole Hurkacz to get closer to returning to the title clash with a 7-6(4) 2-6 6-3 5-7 6-4 win.
He had looked on course to wrap up the match in four sets before ninth seed Hurkacz grew in belief and forced a decider, where Russian Medvedev broke for a 4-3 lead and soaked up the applause before serving out to seal the win.
"I knew how 'Hubi' can play and he played quite well. I felt like the games, almost all of them, probably except 2-0 in the first set, I had a small chance," Medvedev said.
"I managed to take it. Really happy and proud about that. Because with him you don't get many chances."
The former US Open champion has sometimes found it hard to get the Melbourne Park crowd on his side but has received great backing this year and will hope to ride that support when he plays Zverev.
Organisers were able to breathe easier as the day session finished on schedule. On Tuesday, epic matches that involved reigning champion Novak Djokovic and US Open winner Coco Gauff meant the action spilled over into the evening.
Yastremska kept things on track with a swift 6-3 6-4 win over giant-killing Czech teenager Linda Noskova to become the first women's qualifier into the semis since the 1978 event.
The world No.93, who had already taken out Grand Slam champions Marketa Vondrousova and Victoria Azarenka during her stellar run, meets Zheng who came from behind to beat world number 75 Anna Kalinskaya.
"It's nice to make history," said Yastremska, who followed in the footsteps of Christine Dorey, the last qualifier to reach the Melbourne Park semi-finals 45 years ago.
"It's something new for me and for my generation because the last time it happened was a long time ago. I wasn't born yet."
Zheng overcame a slow start to outclass unseeded Russian Kalinskaya 6-7(4) 6-3 6-1 and join Yastremska in the semi-finals of a major for the first time and the Chinese player will also crack the top 10 when the rankings are updated on Monday.
The 21-year-old, who is looking to emulate her idol Li Na and win the Australian Open, expects a thorough test against a player who will be competing in her ninth match of the event.
"It doesn't matter if she comes from the qualifiers," Zheng said. "Right now the people who arrive at the semi-finals, they all have a super level in this tournament."
Reuters
