Novak Djokovic surged into an Australian Open quarter-final clash against Carlos Alcaraz with a dominant victory on Sunday while women's world number one Aryna Sabalenka was a ruthless winner.

Double defending champion Sabalenka is on a collision course with in-form world number three Coco Gauff in the semi-finals in Melbourne if both win in the last eight.

On the hottest day of the tournament so far with temperatures hitting 34 degrees Celsius (93 Fahrenheit), Alcaraz went through when Britain's Jack Draper retired injured.

The 37-year-old Djokovic then kept up his end of the bargain with a 6-3, 6-4, 7-6 (7/4) win over Czech 24th seed Jiri Lehecka in the prime-time match on Rod Laver Arena.

Djokovic is anticipating a "big battle" against Alcaraz on Tuesday.

"The kind of matches that I played against him remind me of my match-ups versus (Rafael) Nadal in terms of the intensity and the energy on the court," he said.

Djokovic appears to be growing into the tournament in an ominous sign for his rivals, as he pursues a record-extending 11th Melbourne crown and historic 25th Grand Slam title.

He dropped a set in each of his opening two matches but has won the previous two in straight sets.

Djokovic and Alcaraz have played each other seven times with the Serb leading 4-3, including victory in their last clash in the Paris Olympics final.

But they have never played at Melbourne Park, where Djokovic has achieved his greatest success.

"When we are seeing him playing, he seems like he's young again... it's unbelievable. He's in a really good shape," said Alcaraz, who has vowed to get a kangaroo tattoo if he wins the Australian Open for the first time.

The 21-year-old Spaniard, who has never gone beyond the quarter-finals in Melbourne, was leading 7-5, 6-1 when Draper pulled the plug.

Draper had come through all three of his previous matches in five sets, and all from 2-1 down, and it appeared to have taken its toll.

"It's not the way I wanted to win, but obviously I'm happy to play another quarter-final here in Australia," said Alcaraz.

The 23-year-old Draper, whose rise has been held back by issues with his body, said his hip injury had been a "ticking time bomb" and he had "multiple areas really in pain".

American 12th seed Tommy Paul destroyed Spain's Alejandro Davidovich Fokina for the loss of just three games as he bids to match or better his semi-final appearance from 2023.

Paul will meet German second seed Alexander Zverev, who survived a mid-match wobble to oust France's Ugo Humbert.

Zverev, who is zeroing in on a maiden Grand Slam title, won 6-1, 2-6, 6-3, 6-2.

Sabalenka warning

Sabalenka blew away Russian 17-year-old Mirra Andreeva 6-1, 6-2 in a chilling warning to sweep into the quarter-finals. 

The Belarusian was out on a roasting center court for only 62 minutes before registering an 18th consecutive win at Melbourne Park.

"I'm super happy to get through this difficult match in straight sets," said Sabalenka, who faces Russian 27th seed Anastasia Pavlyuchenkova next.

Sabalenka struggled with her serve in colder conditions during the first week, but was untouchable as the mercury soared.

"The ball was flying like a rocket," said Sabalenka.

A dangerous Gauff faces Spain's 11th seed Paula Badosa after the American fought back to beat Belinda Bencic 5-7, 6-2, 6-1.

Gauff dropped a set for the first time in 2025 but extended her unbeaten streak to 13 matches going back to last year's WTA Tour Finals.

"Two out of three sets at this stage of my career is not that physically hard for me," said the 20-year-old Gauff, who is chasing a first Melbourne title.

"The off-season I just put in so much work physically so I'm not worried at all about recovering emotionally or mentally."

Badosa declared she "loves" Gauff -- but said that will not prevent her looking for "revenge".

The pair have a 3-3 head-to-head record but Gauff won both their meetings in 2024, with each going to three sets.

The last time was in the semi-finals of the WTA China Open in Beijing, where Gauff won 4-6, 6-4, 6-2 on her way to lifting the title.

by Daniel Hicks