It is not often that Djokovic – who has won 43 of his past 45 matches at Wimbledon – is made to endure such a stern test of his mental resilience on the stage he has dominated on over the past decade.
The sixth seed is through to a 16th Wimbledon quarter-final, second only to the 18 achieved by Federer, but at times it felt as though his progress was under threat.
In a puzzling first set, an out-of-sorts Djokovic had his serve broken three times by De Minaur as the Australian capitalised on his uncharacteristically messy start.
Djokovic was hampered by double faults, with two helping De Minaur go an immediate break up on Centre Court, before he recorded another on his way to going down 4-1.
It appeared he had already turned his attention to the second set when he was again broken to concede the first after 30 minutes on court – and that seemed to be confirmed when he broke his opponent’s serve in the first game.
But Djokovic’s struggles continued, with the Serb eventually falling to a sixth break point in a marathon second game to set the tone for a topsy-turvy second set.