<p> World number one Rafael Nadal takes on Dominic Thiem on Wednesday as he looks for a record-equalling 20th Grand Slam title at the Australian Open.</p>.<p>Nadal has never lost to Thiem at Major tournaments, beating him in the last two French Open finals, but he's taking nothing for granted against the Austrian fifth seed.</p>.<p>"We know each other well. He's a player that I like a lot, the way that he works, the way that he plays, and the way that he tries his best always," Nadal said.</p>.<p>"It is a match that's going to be a tough one, but will be interesting. I know I have to be at my best to have chances."</p>.<p>Nadal and Thiem are playing for a semi-final against Alexander Zverev or Stan Wawrinka, who won the Australian title in 2014 -- the only player outside the Big Three to do so since 2006.</p>.<p>Now ranked 15, the three-time Grand Slam winner said he's playing his best tennis since knee surgery in 2017, with the passion to win another big event still burning bright at 34.</p>.<p>"I've been feeling great on the court, on the practice court, putting a lot of work in physically and tennis-wise," said Wawrinka, who will have to overturn a 0-2 record against seventh seed Zverev.</p>.<p>"Zverev, he's been in the top 10, top five since few years now. It's going to be a difficult match, for sure."</p>.<p>Elsewhere, Wimbledon champion Simona Halep takes aim at the semi-finals when she plays Estonia's Anett Kontaveit, while resurgent Spaniard Garbine Muguruza faces 30th-seeded Russian Anastasia Pavlyuchenkova.</p>.<p>"I'm not thinking negative. I just want to go there and to give my best," said Halep. "This is all I have in my mind."</p>
<p> World number one Rafael Nadal takes on Dominic Thiem on Wednesday as he looks for a record-equalling 20th Grand Slam title at the Australian Open.</p>.<p>Nadal has never lost to Thiem at Major tournaments, beating him in the last two French Open finals, but he's taking nothing for granted against the Austrian fifth seed.</p>.<p>"We know each other well. He's a player that I like a lot, the way that he works, the way that he plays, and the way that he tries his best always," Nadal said.</p>.<p>"It is a match that's going to be a tough one, but will be interesting. I know I have to be at my best to have chances."</p>.<p>Nadal and Thiem are playing for a semi-final against Alexander Zverev or Stan Wawrinka, who won the Australian title in 2014 -- the only player outside the Big Three to do so since 2006.</p>.<p>Now ranked 15, the three-time Grand Slam winner said he's playing his best tennis since knee surgery in 2017, with the passion to win another big event still burning bright at 34.</p>.<p>"I've been feeling great on the court, on the practice court, putting a lot of work in physically and tennis-wise," said Wawrinka, who will have to overturn a 0-2 record against seventh seed Zverev.</p>.<p>"Zverev, he's been in the top 10, top five since few years now. It's going to be a difficult match, for sure."</p>.<p>Elsewhere, Wimbledon champion Simona Halep takes aim at the semi-finals when she plays Estonia's Anett Kontaveit, while resurgent Spaniard Garbine Muguruza faces 30th-seeded Russian Anastasia Pavlyuchenkova.</p>.<p>"I'm not thinking negative. I just want to go there and to give my best," said Halep. "This is all I have in my mind."</p>