That record now belongs to American Arthur Ashe who won as a 31-year-old in 1975.
That would be a first one for Djokovic, who has been the best player on tour for about a decade.
"Sam likes the conditions here". His powerful groundstrokes and big serve have been major weapons on his way to the quarters and will surely be too much for a jaded opponent here. Goes for his shots. He played Grigor Dimitrov in the fourth round and delivered what was arguably his best performance of the tournament so far.
"When he's standing up on the baseline, hitting forehands, dictating, he's a very risky player".
Meanwhile, Andy Murray was defeated by Sam Querrey in five long sets, but we do not think that the outcome would be the same if Murray didn't have troubles with his hip.
He also said the postponement of his last-16 match against Adrian Mannarino, which was pushed a day to Tuesday because of the marathon five-setter in which Gilles Muller beat Rafael Nadal, might have played a role. While he rested up, Murray and Djokovic battled for the world number one spot.
The greatest player of all-time had little trouble against last year's finalist Milos Raonic, beating the Canadian 6-4 6-3 7-6.
Cilic never doubted Wimbledon chances
And Djokovic weighed in on the row by claiming the courts are among the worst he's played on in his 13 years at the All England Club, having frequently complained to the umpire during his match about a hole in the middle of the playing surface. I can look at this quarter-final in a totally relaxed fashion. That was apparently the right move as he dominated the hard-court season in the early part of 2017, which included winning Grand Slam No. 18 at the Australian Open.
Roger Federer and Venus Williams are both really turning back the clock at Wimbledon and playing like they did in much younger days.
Fifteen years after his own Wimbledon fortnight of glory, retired former champion Hewitt fancies seven-time Centre Court king Federer to steer through to the final, and reckons it would make the day more ideal if Murray was on the other side of the net.
Exhausted or not, Djokovic should have his hands full with Tomas Berdych, the 11th seed, on Wednesday.
The second set was even more straightforward as Raonic wafted a forehand wide to concede another early break before Federer's ripped backhand victor caught the line for 5-1.
"The courts are not great this year - I've played on better courts", said Djokovic. In fact, Berdych has failed to defeat the great Swiss since 2013 when he won their Dubai semi-final in three sets. Standing in Muller's way of a semi-final place will be an imposing proposition in the form of Croatian seventh seed Cilic, who has made serene progress through the draw to reach the last eight. He then struck his fifth ace a few games later to close out the set 6-4.
Williams will next face French Open champion Jelena Ostapenko in the quarterfinals.
Djokovic felt sleighted. His fourth round match was delayed because Rafael Nadal's five-set defeat lasted almost five hours.