Alexander Zverev produced a magnificent performance to defeat world No 2 Carlos Alcaraz in a thrilling battle at the Australian Open on Wednesday. The German sixth seed appeared to be racing to victory in the quarter-final clash, taking the first two sets and finding himself 5-2 up in the third. But two-time Grand Slam winner Alcaraz showed his mettle by then winning the next six games on the spin to drag himself back into the match. A deciding fifth set looked on the cards at 4-4 in the fourth until Zverev broke the Spaniard and then held his serve to win 6-1, 6-3, 6-7, 6-4 to seal his first ever win against a top-five ranked opponent in a Grand Slam. “I'm playing one of the best players in the world especially over the last two years. He's been number one and number two in the world and won two Grand Slams,” said Zverev. “When you're up 6-1, 6-3, 5-2 you start thinking... I mean we're all human. It's a huge honour to play against guys like him and then when you're so close to winning, obviously your brain starts going and it's not always helpful but I'm happy that I got it in the end.” Third seed Medvedev admitted his five-set victory over Poland's Hurkacz has left him “destroyed” after a near four-hour fight in sweltering Melbourne heat. Medvedev overcame the ninth seed<b> </b>7-6, 2-6, 6-3, 5-7, 6-4 but admitted he was still feeling the effects of his second-round five-setter against Emil Ruusuvuori, which finished at 3.40am local time in what has been a gruelling tournament. “After every match I'm in the locker room I'm destroyed,” Medvedev said. “But then we do a good job. One day off is probably enough to feel good the next day. “So far, so good, in the beginning of the matches and that's what matters. Then try to win and if you're dead after, doesn't matter because you have a day off.” The Russian – who made the Melbourne final in 2021 and 2022, but lost to Novak Djokovic then Rafael Nadal – admitted he was the type of player who struggled in long matches and the heat. “Sometimes I see some guys, like Hubi [Hurkacz] is one of them, and I see them play five-set matches, 7-6 in the fifth, they seem fine in the locker room,” said the 2021 US Open winner. “I'm, like, 'Wow'. Either maybe it's a question of metabolism and it's genetics. I honestly have no idea. I know I get tired.” Djokovic, looking to win his 11th Australian Open crown and 25th Grand Slam, faces Jannik Sinner in the other last-four clash, also on Friday. In the women's draw, Ukrainian qualifier Dayana Yastremska's dream run continued as she defeated unseeded Czech Linda Noskova 6-3, 6-4. Yastremska, 23, is the first women's qualifier to reach the last four in Melbourne since Australia's Christine Matison in 1978. “It's nice to make history, because at that time I wasn't even born,” said the world No 93, who set up a clash against Chinese 12th seed Zheng Qinwen. “I’m super-happy, very tired.” Yastremska dedicated her win to her country, saying: “I think it's my mission here. I'm just trying to give the signal to Ukraine that I'm really proud of it. “They really deserve huge respect. I always try to write something for Ukraine, about Ukraine.” Zheng came from a set down to see off unseeded Russian Anna Kalinskaya 6-7, 6-3, 6-1. The 21-year-old, known to her fans as “Queen Wen”, had never progressed beyond the quarter-finals in eight previous Grand Slam appearances but held her nerve for the win. “In the first set we had a big competition and the match was really tough for me,” said Zheng, who will move into the world's top 10 when the rankings are updated on Monday. “I just told myself to stay focused, not think any more about the first set and I'm so happy right now, like really excited.” Defending champion Aryna Sabalenka takes on American teenager Coco Gauff in the other semi-final on Thursday when the world No 2 will look to avenge her <a href="https://www.thenationalnews.com/sport/tennis/2023/09/10/coco-gauff-cements-status-as-future-of-american-tennis-with-us-open-triumph/" target="_blank">defeat in the US Open final last September</a>.