The former world No. 1 saw off the Frenchman’s challenge 4-6, 6-3, 6-1, 6-3 win in 2 hours 45 minutes on the Rod Laver Arena. But while he was very happy with the win, he was angry at being made to play in temperatures that hovered around 40 Celsius (104 Fahrenheit), prompting Djokovic to say a safety limit had been reached for the players.
“People might say at this level you have to be as a professional tennis player fit,” Djokovic said.
“It’s the beginning of the season. You work and train hard to be able to sustain these kind of conditions, to be tough.
“But I think there is a limit, and that is a level of tolerance between being fit and being, I think, in danger in terms of health. It was right at the limit.”
The extreme elements made it a desperate struggle just to finish the match with Monfils looking the worse for wear early before Djokovic had enough in the tank to win on his fourth match point in a gruelling eight-minute final game.
“It was brutal conditions and we both suffered, it was a big challenge for both of us,” Djokovic said.
“Gael is one of the best athletes in our sport but he was not at his best in the second and third sets. It was about just hanging in there and try to use every opportunity.”
He pleaded with tournament officials to step in next time the heat gets too much.
“There are certain days where you just have to, as a tournament supervisor, recognize that you might need to give players few extra hours until (the temperature) comes down,” he said.
“I understand there is a factor of tickets. If you don’t play matches, people will be unhappy.”
There were no retirements due to the heat on Day 4, however, and some players were even unfazed by the conditions.
One of those was Roger Federer.
The defending champion had the benefit of an evening start, when the temperatures had cooled. And he made the most of the better conditions brushing past Germany’s Jan-Lennard Struff 6-4, 6-4, 7-6.
Federer, 36, broke serve once in each of the first two sets but had to recover from a break down in the third before sealing victory in the tie-break.
Asked if he had requested an evening match, Federer said: “It’s not my call, it’s [the tournament officials’] call.
“I wouldn’t have minded playing during the day because if you want to get to the top, you’ve got to thrive in all conditions.”
On the victory against Struff, the Swiss sensation added: “I knew about him going in. I’ve practiced with him, played singles and doubles against him too so you have the information you need.”