"I was very, very focused," Nadal said. "I'm very happy with everything and to have another chance on Sunday." That chance will be against 24th seeded Argentine Diego Schwartzman for a place in the quarter-finals. Third seed Dimitrov, who could meet Nadal in the semis, had plenty to prove after a huge second-round fright from a qualifier, who pushed him to five sets. And the Bulgarian delivered in a testing 6-3, 4-6, 6-4, 6-4 win over Russian rising star Andrey Rublev as temperatures touched 40 Celsius (104 Fahrenheit)..@RafaelNadal has dropped only 21 games in three rounds at the #AusOpen
— #AusOpen (@AustralianOpen) January 19, 2018
On-court interviewer: "Is that the best preparation leading into the 4R at a Grand Slam you have ever had?"#Nadal: “I really don’t know. We are gonna check later.” ?#AusOpen pic.twitter.com/LncAO5425E
"These are the most important matches for me, when things are not working for me and I find a way," he said. "I'm feeling good physically, the heat didn't scare me at all today, so that's a good sign." He will next face the winner of an intriguing night match which pits Australian Nick Kyrgios against French veteran Jo-Wilfried Tsonga.Match of the #AusOpen so far? ?@NickKyrgios scores 5⃣ points in a row in the fourth set tie-break to defeat #15 Jo-Wilfred Tsonga 7-6(5) 4-6 7-6(6) 7-6(5) in an epic!
— The Field (@thefield_in) January 19, 2018
Men's singles round-up: https://t.co/lok6It3JhUpic.twitter.com/xiWauNxE4u
Fourth seed Svitolina also kept her title dreams alive by ending the hopes of young teenage pretender Marta Kostyuk. At just 15, Kostyuk was the youngest Melbourne Park third-round contestant since Martina Hingis in 1996, and was hailed after her previous win as "the future of tennis". But she still has a lot to learn with fellow Ukrainian Svitolina handing out a 6-2, 6-2 lesson.Job done! ?
— BBC Tennis (@bbctennis) January 19, 2018
Nadal is through to the #AusOpen fourth round.
He's beaten Dzumhur 6-1, 6-3, 6-1.
Competition updates ? https://t.co/QDzi21z6fy #bbctennis pic.twitter.com/tevYN4tTku
"She's definitely got a bright future," said Svitolina, adding: "It's very special for me to get past the third round." She next plays another qualifier -- big-serving Czech Denisa Allertova who romped past Magda Linette 6-1, 6-4 -- for a place in the quarter-finals on Sunday.Many more to come for this lil champ @marta_kostyuk! Let’s keep it rolling. #last16 @AustralianOpen pic.twitter.com/kflzlEnrgp
— Elina Svitolina (@ElinaSvitolina) January 19, 2018
In a tournament shorn of seeds, 81st ranked Petra Martic also swept into the round of 16, celebrating her 27th birthday by holding off a gritty three-set challenge from Thai qualifier Luksika Kumkhum. Her reward is a match against Belgium's Elise Mertens, who beat struggling Alize Cornet of France in two tough sets. Cornet was among players wilting in the heat, with a doctor taking her blood pressure early in the second set as she succumbed to the baking weather.Question: What did you take from that experience today?@marta_kostyuk: Well, a lot. How much you have to pay Svitolina to have one-hour lesson, so I got it for free.#AusOpen??? pic.twitter.com/9OjX4YnznU
— #AusOpen (@AustralianOpen) January 19, 2018
No matches have been called off or roofs closed at the opening Grand Slam of the year despite the soaring temperatures, with tournament organiser Craig Tiley defending the decision. "These are professional athletes," he said. "We are at the end of the day an outdoor event. We want it to stay an outdoor event as long as possible but at the same time ensuring that the health and wellbeing of players is taken care of." Organisers only activate the extreme heat policy when the temperature exceeds 40 Celsius and the wet bulb globe temperature index hits 32.5 Celsius.Game, set, match!
— #AusOpen (@AustralianOpen) January 19, 2018
Petra #Martic outlasts an impressive Luksika #Kumkhum 6-3 3-6 7-5 to advance to R4.#AusOpen pic.twitter.com/HfjU5XBBhq
On Thursday, Novak Djokovic described the conditions as "brutal", complaining it was hard to breathe. Kyle Edmund joined Nadal in the round of 16, overcoming the elements in a fighting five-set win over Nikoloz Basilashvili and will next play Italian Andreas Seppi who won a battle of the veterans against Croatia's 38-year-old Ivo Karlovic."Try [my] best and survive to the end."
— #AusOpen (@AustralianOpen) January 19, 2018
Petra #Martic braves the tough conditions to book her place in the fourth round. Plays winner of Mertens vs Cornet.#AusOpen pic.twitter.com/SZsEwc8zJQ
Spanish 10th seed Pablo Carreno Busta, a semi-finalist at last year's US Open, also marched on.#AusOpen men’s roundup
— The Field (@thefield_in) January 19, 2018
British hope @kyle8edmund powers through the heat & 5 sets,
#10 @pablocarreno91 downs Mullerhttps://t.co/lok6It3JhU pic.twitter.com/mhWNMdN5Zv
Despite being the second seed, Caroline Wozniacki has not impressed so far. She is the late match on Rod Laver Arena against Dutch 30th seed Kiki Bertens and will play 19th-seeded Slovak Magdalena Rybarikova if she wins.Meanwhile, Marin Cilic has beaten Ryan Harrison 7-6(4), 6-3, 7-6(4) to set a fourth round clash with Pablo Carreño Busta #AusOpen Men's singles round-up: https://t.co/lok6It3JhU
— The Field (@thefield_in) January 19, 2018
[2] @CaroWozniacki enters @RodLaverArena amid a warm reception!#AusOpen pic.twitter.com/EQrFhACzyS
— #AusOpen (@AustralianOpen) January 19, 2018