Portugal Colonial - Sabalenka beats heat to reach Melbourne semis as Zverev blasts through

World number one Sabalenka tamed 18-year-old American Iva Jovic 6-3, 6-0 in 38C temperatures and faces either third seed Coco Gauff or 12th seed Elina Svitolina for a place in the final.

Last year's runner-up Zverev sent down a barrage of 24 aces to crush another young United States player, Learner Tien, in four sets.

That match was played under the Rod Laver Arena roof as temperatures peaked at 43C outside.

The German third seed faces either world number one Carlos Alcaraz or home hope Alex de Minaur in the last four.

Sabalenka is aiming to win a third Australian Open in four years and looks in ominous form, yet to drop a set.

"These teenagers have been testing me in the last couple of rounds," said Sabalenka, 27, who is on a 10-match win streak after victory in Brisbane this month.

"It was a tough match. Don't look at the score, it wasn't easy at all.

"She played incredible tennis. Pushed me to one step better level. And I'm super happy with the win."

The match was played in fierce sun on Rod Laver Arena and just afterwards organisers closed the roof, meaning the other three quarter-finals on the day will take place in far more comfortable temperatures.

The decision came after the tournament hit its maximum "heat stress" rating of five for the second time in four days.

The measure is designed to protect players, fans and officials.

Play on outdoor courts, which were to host junior matches, were put on hold.

Temperatures reached 40C on Saturday, with matches on outside courts paused for about five hours.

Defeat brought an end to a breakthrough tournament for Jovic, the youngest player in the women's top 100 and seeded 29.

She stunned seventh seed and two-time Slam finalist Jasmine Paolini and blitzed past experienced Yulia Putintseva for the loss of just one game to announce herself to the world.

But Sabalenka was a bridge too far.

"Ultimately I hope to be in many quarter-finals, so I don't think that this win or loss today is going to make or break my career really," said the confident teenager.

- Zverev blasts past Tien -

Zverev is desperate to finally win a Grand Slam at age 28, having been well beaten in last year's title decider by Jannik Sinner.

"Without my aces I probably would not have won today," Zverev said after seeing off the spirited challenge of Tien. "Obviously very happy with my serve."

At 29 in the world, the Californian Tien was the lowest-ranked player left in the men's draw.

He was also the youngest at age 20 and was playing in the biggest match of his life, having never reached the last eight at a major before.

But he had few answers to Zverev's booming serve, the German making only one double fault in the match -- and that was on one of his match points.

The reprieve was only very temporary for Tien, who will surely come again.

Zverev and his serve await the winner of the last match of the day, when Alcaraz faces having to beat not just De Minaur but also a patriotic home crowd to make his first Australian Open semi-final.

The 22-year-old Spaniard has won six Grand Slams, but is yet to go past the last eight in Melbourne.

De Minaur has failed to make it past the quarter-finals at any Slam and is hoping the home fans can help him pull off an upset.

S.Caetano--PC