Australian Open: Nadal heats up en route to 4th round

The heat wasn't a factor for Rafael Nadal this time against Damir Dzumhur, despite the searing temperature causing trouble for players earlier Friday at the Australian Open.

Nadal reached the fourth round in Australia for the 11th time with the 6-1, 6-3, 6-1 win, and levelled his career head-to-head record with Dzumhur.

His fellow French Open champion Jelena Ostapenko followed Nadal's match on Margaret Court Arena but didn't make it through to the second week, losing 6-3, 1-6, 6-3 to No. 32-seeded Anett Kontaveit.

The seventh-seeded Ostapenko's loss left only two major winners in the women's draw — and only one of them can reach the fourth round. Five-time major winner Maria Sharapova and former Australian and U.S. Open champion Angelique Kerber are playing each other Saturday.

Nadal had lost his only previous meeting against Dzumhur, when he had to retire because of heat-related issues in the third set at Miami in 2016.

Wozniacki advances

After saving two match points and trailing 5-1 in the third set in her last match, there were no real dramas in the third round for Caroline Wozniacki.

The second-seeded Wozniacki beat Kiki Bertens 6-4, 6-3 to advance to a fourth-round match against Magdalena Rybarikova.

Wozniacki had to save four break points while serving for the match on Friday but clinched it on her fourth match point when Bertens' return of serve went long.

On Wednesday, Wozniacki won the last six games of her match with Jana Fett in the second round.

The former No. 1 Wozniacki is one of four players here who could overtake top-seeded Simona Halep for the No 1. ranking at the end of the Australian Open.

Kyrgios tops Tsonga

It was also a change of scenery for Nadal, who was playing on the No. 2 venue at Melbourne Park while local hope Nick Kyrgios beat Jo-Wilfried Tsonga in a night match on the main court.

Actor Will Smith had a prime position in the crowd to see Kyrgios win for the first time on Rod Laver Arena, taking the last five points in the tiebreaker for a 7-6 (5), 4-6, 7-6 (6), 7-6 (5) victory.

Kyrgios, aiming to be the first home-grown winner of the Australian men's title in 42 years, will next play third-ranked Grigor Dimitrov.

Nadal's fourth-round match is against No. 24 Diego Schwartzman, who beat Aleksandr Dolgopolov 6-7 (1), 6-2, 6-3, 6-3.

15-year old Kostyuk ousted

The youngest player in the tournament and the oldest player in the men's draw went out earlier on Day 5.

Fourth-seeded Elina Svitolina ended 15-year-old Marta Kostyuk's run with a 6-2, 6-2 victory.

"She's a great fighter," Svitolina, one of five women in contention for the No. 1 ranking, said of her fellow Ukrainian. "We're going to hear a lot more about her."

Svitolina will next play Denisa Allertova. No. 19 Magdalena Rybarikova had a 7-5, 3-6, 6-1 win over Kateryna Bondarenko.

Andreas Seppi withstood 52 aces from 38-year-old Ivo Karlovic for a 6-3, 7-6 (4), 6-7 (3), 6-7 (5), 9-7 win in 3 hours and 51 minutes in the afternoon.

'Dangerous' heat continues

Players were bothered and spectators clamoured for shade and mist-spraying fans in searing heat earlier Friday, and organizers were on the verge of enforcing the tournament's extreme heat policy before temperatures dropped significantly after peaking at 40 Celsius (104 F) around 2 p.m. local time.

Alize Cornet, who had her blood pressure checked during a medical timeout in her 7-5, 6-4 third-round loss to Elise Mertens, was among those calling for a review of the limits that determine when play should be suspended.

"I started to feel dizzy. ... I was feeling super, super hot. I kind of felt that I could faint at any moment," she said. "Playing in this condition is of course very dangerous for the health of the player."

She got some support from Nadal, who said the conditions were "very, very tough" but the Australian Open wasn't the only tournament affected by high summer temperatures and at least it wasn't humid.

"Sometimes is too much and can become little bit dangerous for health," he said. "It's not nice to see players suffering that much on court."

Dimitrov beat No. 30 Andrey Rublev 6-3, 4-6, 6-4, 6-4 in just over three hours after the change came through and said "the heat didn't scare me at all today."

Kyle Edmund overcame Nikoloz Basilashvili 7-6 (0), 3-6, 4-6, 6-0, 7-5 in 3 1/2 hours on an open court in the peak of the heat, earning a spot in the next round against Seppi. No. 10 Pablo Carreno Busta beat No. 23 Gilles Muller and will next play No. 6 Marin Cilic, a 7-6 (4), 6-3, 7-6 (4) winner over Ryan Harrison.​

Petra Martic celebrated her 27th birthday with a 6-3, 3-6, 7-5 over Thai qualifier Luksika Kumkhum.

"That was really ugly," Martic said of the heat. "You need to be mentally tough and ready to just suffer out there."