Chung showed another sign of his promise by coolly closing out a five-set win over German fourth seed Alexander Zverev, a player many pundits have widely tipped as a future grand slam victor.
The Frenchman remarkably recovered to make a fight of it before a relieved Djokovic, seeded 14, came through 4-6, 6-3, 6-1, 6-3.
But No 13 seed Sam Querrey was not so fortunate.
I think with that, she played extremely well.
Federer will meet French 29th seed Richard Gasquet for a place in the last 16 as he continues his bid for a 20th grand slam title.
In the mens draw, Alexander Zverev became the highest mens seed to exit as the No. 4 was toppled 5-7, 7-6 (7-3), 2-6, 6-3, 6-0 by Chung Hyeon.
Suarez Navarro moved on to the quarterfinals today after beating Anett Kontaveit 4-6, 6-4, 8-6.
"We're high-level athletes capable of pushing the limits very far and sometimes too far, that's why I say that it could be risky".
Argentinean Juan Martin del Potro fired 60 winners on his way to a 6-4 7-6 (4) 6-7 (0) 6-4 second-round victory over Karen Khachanov of Russian Federation.
David Goffin was the biggest name to fall as he was undone by Julien Benneteau.
In 2016, players were taken off the courts during the opening round of qualifiers, while Canadian Frank Dancevic complained about the open's "inhuman" conditions in 2014.
The 26-year-old said: "Definitely it was a very tough match".
"It was tough conditions, brutal, especially the first 90 minutes", he said.
As for the match itself, Djokovic said the match went just about how it would when playing under insane conditions.
As the thermometer headed towards an energy-sapping 40C and reports of 69 degrees being measured on the court surface, Djokovic and his opponent Gael Monfils took to a sun-baked Rod Laver Arena for their second-round clash.
"I love being in the city", said Sharapova.
"We just hope they (Slams organisers) realise and they do appreciate us maybe more all the time and not just in waves, you know what I mean?"
"As fantastic as that run was, the combination of being exhausted from that and having a wrist that still wasn't 100 percent ideal, I just needed to kind of shut it down, calm down", she said.
"I'm sick to the stomach. And, you know, I'm just going to go out there and do my best".
However, Thiem broke him five times over the course of the rest of the match in typically gutsy fashion to take an epic encounter 6-7, 3-6, 6-3, 6-2, 6-3.
"I wanted to start with the right intensity, which I have", he told the cheering crowd afterwards.