LONDON -- Novak Djokovic shrugged off a slow start to power past unseeded Australian Alexei Popyrin 4-6, 6-3, 6-4, 7-6(3) and into the Wimbledon fourth round Saturday.
Djokovic's bid for a record-extending 25th Grand Slam title looked under threat when Popyrin took a 4-3 lead with a blistering crosscourt forehand winner and sealed the opening set with a second-serve ace.
"It was another tough match. I didn't expect anything less than what we experienced on the court today from Alexei," said Djokovic, who was also taken to four sets by Popyrin at this year's Australian Open. "I know he was going to come to the match with confidence, a lot of self-belief. He was close to winning (when we played) in Australia earlier this year."
Appearing rejuvenated after the roof was closed, Djokovic went 4-1 up in the second set. Then, fans erupted on Centre Court as news trickled through about England beating Switzerland to make the Euro 2024 semifinals.
The amused second seed simulated a penalty kick that Popyrin pretended to save to the delight of fans.
Djokovic had little trouble in the second and third sets but faced more resistance in the fourth. Popyrin dug deep in search of his first win in the pair's third meeting, saving three break points to hold on in the 11th game.
After ensuring a tiebreak, however, Djokovic switched on the afterburners to close out the win, finishing with a fiery serve that Popyrin sent into the net.
"I played a good second and third set and the fourth was anybody's game," Djokovic said.
"He was serving very well. It was very difficult to read his serve. It was just a very challenging match, mentally as well to hang in there.
"I'm not allowed to have too big concentration lapses. I think I've done well in that regard in one of the best tiebreaks I've played this year, that's for sure."
Djokovic arrived at Wimbledon weeks after having surgery on his right knee, which he injured at the French Open. He said he was getting better with every match.
"My feeling of movement, confidence particularly extreme balls, reaching, sliding. I definitely got better today than in my second match," Djokovic said, referring to his four-set win over unseeded Briton Jacob Fearnley.
"Hopefully the direction or trajectory will keep going in a positive way. Let's see what happens in the next one."
Up next for Djokovic is 15th seed Holger Rune, who advanced after coming back from a two-set deficit against Quentin Halys on Saturday.
Reuters contributed to this report.