Tennis rackets are not the only thing on court that are highly strung, as Novak Djokovic often shows.
The 24-time Grand Slam champion lost his cool at Wimbledon on Thursday as he demanded a fan be removed from court.
Djokovic has not fully explained what went on, but something got to him.
And it would not be the first time that has happened, especially on the biggest stage of all.
During the 2023 Wimbledon final, where he was bidding for a record equalling fifth successive title, he had a complete meltdown.
It was his racket this time that got the full force of his frustration.
The Serbian saw red after losing his serve in the fifth set against Carlos Alcaraz as he saw his title hopes slipping away.
He smashed his racket against the net post and was immediately reprimanded by the umpire, who gave him a code violation.
Djokovic was subsequently fined more than £6,000 for that moment.
On that, he said: “There’s not much to talk about that. Second one was frustration. I had break points in the second game.
“Yeah, just tough, tough couple of points. He played amazing to break my serve, which was enough to win the fifth.
“The first one was the time violation, so yeah. Not a great moment again, but you just kind of have to accept it.”
For now, however, he will be hoping to avoid any repeats at Wimbledon in 2024.
He is through to the third round after beating Jacob Fearnley on Thursday, despite dropping one set.
Djokovic will face Alexei Popyrin in third round as he bids for an eighth title at the All England Club.
Speaking on court afterwards, Djokovic said: “First and foremost, huge congrats to Jacob for an amazing match today, he put in a great effort, played very good tennis.
“He deserves a great round of applause. I haven’t had a chance to see him play, actually two days ago I’ve seen him for the first time.
“Obviously there’s always an element of surprise and, you know, nothing to lose, him playing in Wimbledon, it’s always going to be tough. Most of the British players grow up being exposed to grass courts, quick surfaces, so they know exactly how to play.
“[It was a] very windy day, very challenging conditions, I thought he served very well, it was very difficult to break his serve.
“He made me work, definitely, I was probably a but lucky in the fourth to not go a break down. Maybe I could have won the match in three, but I think all in all potentially this match deserved to get into the fifth the way we both played, the way he played, especially in the fourth – but very glad it didn’t.”
He continued: “I don’t know if I really had a champion’s mentality today.
“I was not really comfortable in my own skin, particularly in the third and fourth, but sometimes you have rough days where maybe you’re not feeling your best. And of course it also depends on the opponent across the net.
“Today Jacob played on a high level and made me earn this victory. All in all, it was a win, I’ll take it and hopefully I can play better in the next round.”
Djokovic is in an unusual position at Wimbledon this year not being the favourite, in part because of a knee injury that required surgery just a month ago.
He is still wearing a knee brace – that seemingly broke the Wimbledon dress code rules.
However, he insists that his injury is feeling good at the moment.
“Honestly I was feeling okay,” he said. “I don’t want to be looking for any excuses for my performance today. Again, credit to Jacob. On my side, I should have done some things better when I was a break up in the third. As I said, very swirly, very challenging conditions on the court.
“I think physically I felt well. Can I be playing better and moving better? Yes, absolutely, so I’m hoping that as the tournament progresses, I’ll be feeling a bit better.”