Everyone should know by now to never count out Novak Djokovic.
No matter how big a deficit he faces. No matter how poorly he might be playing.
And so it made sense that Djokovic would manage to come all the way back from a two-set deficit to beat Laslo Djere 4-6 4-6 6-1 6-1 6-3 in the third round of the US Open, avoiding what would have been his earliest exit there since 2006.
"Trust me, it was nerve-racking all the way until the last shot," Djokovic said.
The match began under the lights in Arthur Ashe Stadium on Friday night and did not wrap up until more than 3-1/2 hours later, concluding just after 1:30am (EDT)
It was Djokovic's eighth career victory after dropping the opening two sets of a match. He also improved to 38-11 in five-setters over his career.
Once he seized control, he held on tight and never let Djere recover.
In the crucible of a fifth set, Djokovic was cool as can be, collecting 12 of the initial 14 points to leave no doubt how this would go.
Djokovic is seeded No. 2 in New York behind Carlos Alcaraz, and pretty much everyone has been expecting the two of them to meet for the championship on September 10.
That would be a rematch of their riveting final at Wimbledon in July, which Alcaraz won in five sets.
That appeared as if it might be derailed by Djere, a 28-year-old who is also from Serbia and was seeded 32nd in New York.
This would have been by far the biggest victory of his career:
When it ended, they met at the net for a hug.
"I didn't have much options in the beginning, but in the third, I kind of lifted myself up," Djokovic said.
"Once I got the break in the third, I thought, 'OK. I have a shot. I have a chance. I might as well go after it. ... I started to read his game more than I did in the first two sets."
Tommy Paul earned a debut appearance in the fourth round at the Open by hitting 15 aces and getting broken just once during a 6-1 6-0 3-6 6-3 win over No.21 Alejandro Davidovich Fokina of Spain in Arthur Ashe Stadium.
"I was kind of, like, 'really, they're putting me on Ashe?' I knew there was a pretty strong schedule of people," said Paul, who never before had played in the 23,000-seat main stadium.
"I was kind of surprised. ... hopefully I'll be back many more times."
At least one American is now guaranteed a spot in the quarter-finals, because 26-year-old Paul's next opponent is unseeded Ben Shelton, a 20-year-old from Florida.
Shelton advanced Friday by defeating Aslan Karatsev of Russia 6-4 3-6 6-2 6-0 with the help of 26 aces.
Also into the fourth round is No.10 seed Frances Tiafoe, who was a 4-6 6-2 6-3 7-6 (8-6) winner against No.22 Adrian Mannarino of France.
The 25-year-old Tiafoe is the first man from the United States to get to the fourth round in New York for four consecutive years since Andre Agassi in 2002-05.
Also in the round of 16 is Australian wildcard Rinky Hijikata, who fought off a fightback from Chinese trailblazer Zhizhen Zhang to post a 6-3 6-3 4-6 6-3 win.
Dominic Stricker also went through by beating Frenchman Benjamin Bonzi 2-6 7-5 7-6 (7-4) 3-6 6-2.
The Swiss will now meet No.9 seed Taylor Fritz, who toppled Jakub Mensik 6-1 6-2 6-0.