The World No.2 lost the first set against the Austrian in London and reacted by slamming a ball into the crowd – forcing the umpire to give the Serbian an official warning for unsportsmanlike conduct.

Djokovic was asked about his behaviour in his post-match press conference and took offence to the line of questioning.

“You guys are unbelievable. You’re always picking these kind of things,” Djokovic said.

“I’m the only player that shows his frustration on the court? That’s what you are saying?”

Has Novak lost the plot?

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