Maybe the Centre Court spectators were saluting Novak Djokovic's opponent by saying his name. Maybe they were booing Djokovic, trying to rattle him. The 24-time Grand Slam champion was sure it was the latter — and he let everyone know he was not happy about it.

Djokovic easily beat 15th-seeded Holger Rune 6-3, 6-4, 6-2 in just over two hours Monday night to reach the Wimbledon quarterfinals, then made sure to get a message across to those fans he thought were against him.

Rune's supporters at various tournaments will often stretch out his last name, chanting, "Ruuuuuune!" — which sounds rather similar to "Boooooo!" — and that happened again Monday.

During his on-court post-match interview, Djokovic spoke briefly about the match, but then veered into a discussion about the people in the stands.

"To all the fans that have respect and that stayed here tonight: Thank you very much from the bottom of my heart. I appreciate it. And to all those people that have chosen to disrespect the player — in this case, me — have a goooood night. Gooooood night. Gooooood night. Very gooooood night," he said, stretching out the "Os" in "good" so they sounded like "boo."

The interviewer tried to dissuade Djokovic from thinking anyone was trying to taunt him.

"They were. They were. They were. I don't accept it. I know they were cheering for Rune. But that's an excuse to also boo," Djokovic said. "Listen, I've been on the tour for more than 20 years. So trust me, I know all the tricks. I know how it works. It's fine. It's fine. It's OK. I focus on the respectful people, that have respect, that paid (for) a ticket to watch tonight — and love tennis. And appreciate the players and the effort that the players put in here."

At his news conference later, Djokovic was asked whether he thinks the All England Club should do something to curb rowdy fan behavior.

"Look, I don't know what Wimbledon can really do about it. I mean, in those particular moments when it happens, the crowd paid their tickets. They have the right to be there and cheer the way they want to cheer. That's absolutely something they choose — how they behave or how they choose to support the player is really up to them," Djokovic responded.

"Yes, you could argue maybe a chair umpire or whoever can step in at certain moments and calm them down, but there's not much you can do. You're not going to take out the whole section of the crowd or stadium because they're misbehaving or showing disrespect."

Rune — who got off to a terrible start in the match, dropping the first 12 points — didn't make much of it all.

"If you don't know what was happening, probably it sounded like 'boo,'" he said.

"He was just better than me today," Rune said. "Whether the crowd was this or that, I think it was great support for both players, to be honest."

When the match ended, Djokovic gestured with his racket, as if he were playing a violin. While he explained that it was a tribute to his daughter Tara, some might have seen it as a playful dig at anyone in the arena that had been rooting against him as he reached the quarterfinals at the All England Club for the 15th time.

He has won the championship at Wimbledon seven times and was the runner-up to Carlos Alcaraz last year.

"I have played in much more hostile environments, trust me," Djokovic said. "You guys can't touch me."

One leg

It was a strange way to end proceedings on Centre Court which had earlier witnessed world No 4 Alexander Zverev becoming the highest men's seed to fall by the wayside. The German came unstuck against Taylor Fritz in a five-set thriller despite being only two games away from securing a place in the last eight for the first time.

Like Djokovic, who had knee surgery last month, Zverev turned up on court wearing a protective support around his leg after falling awkwardly during his previous match.

That did not stop the German trading brutal blows with Fritz for three-and-a-half hours before he fell to a 4-6, 6-7 (4), 6-4, 7-6 (3), 6-3 defeat after finally being broken for the first time at this year's championships, having chalked up 56 successive holds of serve.

Zverev regularly bombarded his American opponent with 210 km/h missiles, fired down 19 thunderbolt aces, produced 55 winners, and even won the longest rally in the contest, which dragged on for 21 shots — and at the end of it all, the German declared he had been playing "on one leg".

"It was fairly obvious that I wasn't 100 percent today, right?" Zverev asked reporters before elaborating that an MRI scan had shown that he had a tear in his knee capsule as well as bone bruising.

"There weren't really long rallies because I couldn't play long rallies. Credit to him that he came back, but it wasn't a great tennis match."

The Fritz-Zverev marathon was the 35th match to go five sets at the All England Club this year, tying the record for the most at any slam since tennis turned professional in 1968.

Eastbourne champion Fritz's victory also raised a glimmer of hope that the 21-year Grand Slam drought for American men might soon end after he joined Queen's Club champion Tommy Paul in the last eight.

For the first time since 2000, more than one American man will feature in the Wimbledon quarterfinals.

It was not a good day for Frenchmen, however, as Alex De Minaur beat Arthur Fils 6-2, 6-4, 4-6, 6-3, while Italian Lorenzo Musetti set up a showdown with Fritz after gatecrashing Mpetshi Perricard's 21st birthday celebrations with a 4-6,6-3, 6-3, 6-2 win.

Agencies