World tennis’s crankiest player has staged his most spectacular tantrum yet, and is paying the price in both dollars and reputation.

Nick Kyrgios was defaulted at the Italian Open after he slammed his racquet into the ground, kicked a water bottle, tossed a chair onto the court and then walked off.

The fiery Australian, 24, currently ranked 36 in the world, was playing Norway’s Casper Ruud in a second-round match when he shouted at one or more unknown people in the crowd for disrupting his serve. After receiving a one-game penalty for unsportsmanlike conduct, he erupted.

Kyrgios was fined €20,000 (A$32,458) and forfeited all his ranking points, and €33,635 (A$54,590) in prize money from the tournament. He could also be suspended from the game for a period of time. Ruud himself suggested after the match that Kyrgios should serve a suspension of at least six months.

Later in the day Kyrgios posted a somewhat apologetic message on Instagram:

It’s the latest wild outburst by the player widely regarded as the modern-day successor to 1980s serial misbehaver John McEnroe, with a long series of fine for poor behaviour.

And it comes just days after an interview with tennis journalist and podcaster Ben Rothenberg in which Kyrgios described Novak Djokovic as having “a sick obsession with wanting to be liked”.

“He just wants to be like Roger [Federer],” Kyrgios told Rothenburg. “For me personally – I don’t care right now, I’ve come this far – I feel like he just wants to be liked so much that I just can’t stand him.

“This whole celebration thing that he does after matches, it’s like so cringeworthy. It’s very cringeworthy.”

Kyrgios also described Djokovic as “an unbelievable player … one of the greatest we’ll ever see” and predicted he would surpass Federer’s Grand Slam tournament win record.

But he added: “No matter how many Grand Slams he wins, he will never be the greatest for me. Simply because, I’ve played him twice and like, I’m sorry, but if you can’t beat me, you’re not the greatest of all time.”

In the same interview with Rothenberg, Kyrgios described Rafael Nadal as “super salty”.

“When he wins, it’s fine. He won’t say anything bad, he’ll credit the opponent, ‘He was a great player.’

“But as soon as I beat him, it’s just like, ‘He has no respect for me, my fans and no respect to the game.’”