A “very hot-headed” Novak Djokovic produced a vintage display to join Carlos Alcaraz and Alexander Zverev in the Australian Open last 16 on Friday, but Naomi Osaka’s bid for a third Melbourne crown is over with injury. Also on day six, women’s defending champion Aryna Sabalenka “pushed to the limit” to set up an intriguing showdown with teenage talent Mirra Andreeva. Red-hot Coco Gauff was an emphatic winner once again to underline her title credentials. Djokovic, who is chasing a record-extending 11th Melbourne title and historic 25th Grand Slam crown, is on a collision course with Alcaraz in the quarter-finals. Both kept that tantalising prospect alive with ruthless victories. Under new coach and old rival Andy Murray, the 37-year-old Djokovic needed four sets in both of his opening two matches. But not this time, swatting aside Czech 26th seed Tomas Machac 6-1, 6-4, 6-4 and letting out a roar at the end. Djokovic also pointed to his ear and then someone in the Rod Laver Arena crowd. “I am very hot-headed right now,” said the fiery Serb, but added: “This is definitely the best match I’ve played in the tournament.” Djokovic, who needed a medical break in the second set and used an inhaler, faces 24th seed Jiri Lehecka next. Spain’s Alcaraz, who raced into the last 32 for the loss of just 12 games, suffered a wobble in the third set against Portugal’s unseeded Nuno Borges. But the third seed, who has won four majors but never been beyond the quarter-finals in Melbourne, regained his focus to ease through 6-2, 6-4, 6-7 (3/7), 6-2. The 21-year-old knows how he plans to celebrate if he wins the tournament for the first time. Alcaraz, who is sporting a new buzz cut in Melbourne, vowed to get a kangaroo tattoo if he goes all the way.