He defeated Adrian Mannarino in three sets 6:2, 7:6 (5), 6:4.
On Saturday, his former coach Boris Becker said he had witnessed enough in the first week of Wimbledon to confirm that the Serb has rediscovered his love for the sport."Boris knows me very well".
Djokovic said that forcing players to battle marathon matches led to an unfair competition as the victor may have to return the following day to play. Grass is probably the most complex surface to maintain.
It was, as so much of the match had been, the favourite's backhand against the lefty's forehand but this time it went the way the crowd had expected, Mannarino finding the net as Djokovic marched on to the last eight.
Djokovic needed treatment on his right shoulder after the fifth game of the third set and a medical timeout at 4-3 to treat the same problem. He said he found a large hole near the service line of Centre Court on Tuesday and showed it to the chair umpire. If I'd taken on a young player - you mould those players off the court, on the court.
The schedule has also been brought forward to 12pm so as not to delay the two scheduled quarter-finals, although there are concerns about inclement weather and its effect on the two quarter-finals scheduled on No. 1 Court. When he finally won the set, he turned to his coaches, Andre Agassi and Mario Ancic, and yelled loudly, nearly as if to exhort them as much as himself.
Both players served well but Novak was more effective behind his initial shot, to face only 2 break points in the entire match.
The leading betting company in terms of live streaming, Bet365 showcase over 70,000 events every year, including some of the biggest football matches of the season. Nadal is no longer in the tournament, and Djokovic will face No. 11 Tomas Berdych on Wednesday.
And while he acknowledged the challenge conditions have posed, Djokovic, a three-time singles champion at the All England Club, has made no attempt to disguise his displeasure at being presented with a sub-par stage on which to perform.
Novak Djokovic noticed the ball bouncing differently in some patches.
Mannarino has never reached the quarter-final of any Grand Slam with his best being a fourth round finish at Wimbledon in 2013.
With the score at 5-4 and Djokovic serving for the match, Mannarino managed one final heave and pushed Djokovic to deuce once more and one final rally.
That match lasted nearly five hours, with 28 games played in the fifth set.