Australian Open updates: Novak Djokovic, Coco Gauff, Aryna Sabalenka and Jannik Sinner win on day 10

Defending Australian Open champions Novak Djokovic and Aryna Sabalenka are through to the semifinal at Melbourne Park after securing wins on Tuesday.

Djokovic was tested by American 12th seed Taylor Fritz over four sets, while Sabalenka was clinical in her straight-sets victory over Czech ninth seed Barbora Krejcikova.

The defending champions will now face Italian Jannik Sinner and American star Coco Gauff respectively, in their semifinals.

Djokovic, who has won the Australian Open all 10 times he has previously passed the quarterfinal stage, was agitated at times during the three-hour-and-45-minute battle, before reaching his 48th grand slam semifinal with a 7-6(7-3), 4-6, 6-2, 6-3 victory.

“I suffered a lot in the first couple of sets (and) also due to his high-quality tennis,” Djokovic said.

“He was serving well, he was staying close to the line, he was really suffocating me from the back of the court.

“It was extremely hot while the sun was still out there — physically very draining (and) emotionally as well.”

The king of Melbourne Park could not convert any of his first 15 break point chances but broke his duck early in the third set before doing it another three times.

“Conversion of break points was really poor,” Djokovic said of his four-for-21 success rate.

“But, at the end of the day, I managed to break him when it mattered in the third and the fourth.

“I upped my game probably midway through the third set all the way to the end. I served extremely well … I had even more aces (20 to 16) than he did, which is a surprise stat.”

Djokovic has drawn within two wins of clinching an unprecedented 25th grand slam that would lift him past Margaret Court’s magic mark of 24, which has stood since 1973.

Meanwhile, Sabalenka demolished Krejcikova in a one-sided contest.

In a match that started more than two hours, the world number two put on another clinic at Rod Laver Arena to win 6-2, 6-3 in 71 minutes.

Sabalenka has dropped just 16 games and won every set across her five matches.

The 25-year-old did drop a service game late in the second set but still cruised to a 12th-straight victory at Melbourne Park.

“It was a really great match and I played really great tennis and I hope I can just keep playing that way or even better,” Sabalenka said.

“I’ve been working so hard last year and this pre-season, I think it’s all about hard work on the practice court so you’re ready for the matches.”

The Belarusian is aiming to become the first woman since countrywoman Victoria Azarenka in 2012 and 2013 to win consecutive Australian Open titles.

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AAP/ABC

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