MELBOURNE, Australia >> First came the medical timeouts, one each for Jannik Sinner and Holger Rune with the temperature above 90 degrees Fahrenheit at the Australian Open.

Then came the bizarre sight of a 20-minute delay because the net at Rod Laver Arena detached from the court after being hit by a big Sinner serve.

In the end, the breaks in action were “lucky,” Sinner said, because they gave him a chance to catch his breath, put his struggles aside and emerge with the victory — as he keeps doing, no matter the site or the circumstances. The defending champion moved into the quarterfinals at Melbourne Park on Monday by eliminating the 13th-seeded Rune 6-3, 3-6, 6-3, 6-2.

“I don’t want to talk so much (about) how I felt today. I was not feeling really well. I think we saw that today. I was struggling physically,” Sinner said, declining to say exactly what was wrong.

The No. 1-ranked Sinner occasionally tried to cool off by pressing a cold towel to his face or pouring water down the back of his neck. He was far better down the stretch, both after a 10-minute-plus delay in the third set, when he went to the locker room for medical attention, and after a 20-minute holdup in the fourth when the screw connecting the net to the blue playing surface came undone.

Sinner has won 18 consecutive tour-level matches dating back to late 2024. Last season, he went 73-6 with eight titles, the first man with that many tournament championships in a single year since Andy Murray in 2016.

That haul included Sinner’s first two Grand Slam trophies, at the Australian Open in January and the U.S. Open in September — the latter shortly after he was exonerated for testing positive for an anabolic steroid twice in March. His case is still unresolved, though, with a hearing scheduled for April in the World Anti-Doping Agency’s appeal of the ruling.

Sinner will play No. 8 Alex de Minaur of Australia, who defeated unseeded Alex Michelsen of the U.S. 6-0, 7-6 (5), 6-3 at night to reach the quarterfinals at his home Grand Slam tournament for the first time. A second Italian joined Sinner in the quarterfinals when 55th-ranked Lorenzo Sonego got that far at a major tournament for the first time by ending the run of American qualifier Learner Tien 6-2, 6-3, 3-6, 6-1.

Sonego will go up against No. 21 Ben Shelton, who advanced when 38-year-old Gael Monfils of France quit because of an injury early in the fourth set. The 22-year-old American was leading 7-6 (3), 6-7 (3), 7-6 (2), 1-0 after nearly three hours when Monfils, who is married to Svitolina, called a halt to the match.

The men’s quarterfinals Tuesday will be Novak Djokovic vs. Carlos Alcaraz, and Alexander Zverev vs. Tommy Paul.

Keys, Swiatek move on

In the women’s fourth round, 2017 U.S. Open runner-up Madison Keys eliminated 2022 Wimbledon champion Elena Rybakina 6-3, 1-6, 6-3, and now plays Elina Svitolina, a 6-4, 6-1 winner against Veronika Kudermetova. Five-time major champion Iga Swiatek had — no surprise here — an easy time beating “lucky loser” Eva Lys 6-1, 6-0 in just 59 minutes.

Swiatek, who will face No. 8 Emma Navarro next, compiled a 28-7 edge in winners and has ceded a grand total of 11 games through four matches in the tournament. Contrast that to Navarro’s path: Her 6-4, 5-7, 7-5 win against No. 9 Daria Kasatkina was the American’s fourth three-setter in four matches in Melbourne, and she has dropped more than 60 games while spending more than 10 hours on court.

Djokovic gets apology

Djokovic got the mea culpas he wanted from the Australian Open’s local broadcaster and its employee who insulted him on the air and so, according to tournament organizers, the 24-time Grand Slam champion is ready to concentrate on his quarterfinal showdown with Carlos Alcaraz.

“Novak acknowledges the apology has been given in public as requested,” read a statement issued Monday by Tennis Australia, “and is now moving on and focusing on his next match.”

After winning at Rod Laver Arena on Sunday evening to set up the contest against No. 3 Alcaraz, Djokovic declined to do the customary post-match on court TV interview. Later that night, at his news conference, Djokovic explained that he was protesting comments made by Tony Jones on Channel 9 on Friday.

Djokovic, a 37-year-old from Serbia, did not name Jones, but said a “famous sports journalist who works for official broadcaster Channel 9 ... made a mockery of Serbian fans and also made insulting and offensive comments toward me.”

Jones called Djokovic overrated and a has-been and made what seemed to be a reference to when the player was deported from Australia in 2022 because he was not vaccinated against COVID-19.

Djokovic added that he would continue to avoid speaking to the network without an apology from it and Jones, which arrived on Monday.

Nine Network said in a statement it apologized “for any offense caused from comments made” while live on air.

During an appearance on a TV show Monday, Jones said he intended his words as “banter” and apologized to Djokovic “if he felt that I disrespected him.”

“I considered it to be humor,” Jones said, and also offered words to Serbians.

“I do feel as though I’ve let down the Serbian fans,” he said.

Swiatek’s ruling stands

Swiatek’s one-month suspension for failing a drug test will not be appealed by the World Anti-Doping Agency because her explanation “is plausible,” WADA announced on.

“Well, for sure, I’m just satisfied that I can get closure, kind of,” Swiatek said, “and I can just move on and finish this whole process, because I just want to play tennis and focus on the tournament.”