Djokovic had won the past four major titles in a row — and was halfway to the first calendar-year Grand Slam for a man since Rod Laver in 1969.
"I believe in positive things in life, and I managed to win four Grand Slams in a row — two different seasons, though. I want to try to focus on that," the No. 1-seeded Djokovic said, "rather than failure."
Djokovic last exited as early as the third round at any major tournament all the way back in 2009, when he departed the French Open at that stage. He made at least the semifinals at Wimbledon every year since 2010.
Yet things began looking bleak for Djokovic when the match began Friday and he dropped the first two sets against Querrey, an American ranked 41st. Djokovic, normally so consistent, so efficient, never quite seemed to be himself, and after the match, asked whether he was 100 percent healthy, the 29-year-old Serb replied: "Not really, but it's not the place and time to talk about it."
Still, after play was halted Friday evening by rain — a recurring theme in this contest and the tournament as a whole — Djokovic came back out Saturday and played much better at the outset.
"He's on his way to possibly being the best ever," Querrey said, "and so you know he's mentally tough and he was going to come back."
Djokovic took the third set, then went up a break in the fourth at 5-4 by pounding a forehand winner that brought coach Boris Becker to his feet. But serving to even the match at two sets apiece, Djokovic faltered.
That game included two calls against Djokovic which, according to the BBC broadcast, were incorrect — but he was out of challenges and so couldn't ask for a review. Querrey, 0 for 6 on break points in the set until then, converted No. 7 when Djokovic's poor forehand volley found the net for 5-all.
After Querrey held for 6-5, Saturday's third rain delay arrived. When they resumed, Djokovic got to a tiebreaker, which he led 3-1. But Querrey hung in there, and a stray forehand by the big favorite sailed wide to end it.
"He overpowered me," Djokovic said.
It's the first loss for Djokovic at any major tournament in more than a year: He was beaten by Stan Wawrinka in the French Open final in June 2015. Since then, Djokovic won Wimbledon last July, the U.S. Open in September, the Australian Open in January, and the French Open last month.
How surprising was this result? Djokovic owns a total of 12 Grand Slam titles — including each of the past two at Wimbledon — while Querrey has never made it past the fourth round at any major. Plus, Djokovic won 8 of 9 previous head-to-head meetings.
Compare their past records at the All England Club: Both entered with the same number of losses at the event, eight, but the difference in wins was the not-so-insignificant tally of 54 for Djokovic to nine for Querrey.
Now make that 10 for the 28-year-old Querrey, who smacked 31 aces against Djokovic, widely considered the top returner of his era — and perhaps any.
"He served very well, as he usually does," Djokovic said, "and I think that part of his game was brutal today."
Querrey reached a career-best ranking of No. 17 in 2011, but he's never quite lived up to the potential his big serve and forehand appeared to promise when he was younger. They were on-target Friday, building that lead during 72 minutes of action before rain at 8 p.m. On Saturday, 16 hours later, Djokovic and Querrey stepped back out on the grass at No. 1 Court.
Djokovic woke up Saturday — if he'd been able to sleep at all, that is — knowing he would need to win three sets in a row in order to extend his Grand Slam quest. His winning streak at tennis' four most important events was the longest in the Open era and third-longest in history, trailing Don Budge's run of 37 victories in the 1930s and Laver's run of 31 in the 1960s.
In the Open era of professional tennis, which dates to 1968, Djokovic is only the second top-seeded man to lose in the third round at Wimbledon: Coincidence or not, the other was Jim Courier in 1992, when he, too, was halfway to a true Grand Slam.
When Djokovic was asked how much the weight of history burdened him, he said: "I don't think it played (that) big of a factor, to be honest."