Wilander had questioned three-time Grand Slam winner Andy Murray’s decision to take a wildcard spot at the French Open, after the Briton was beaten 6-1, 6-3, 6-2 in the first round by Stan Wawrinka.

"Is it his right to be out there doing that? Why?" Wilander, a seven-time men's Grand Slam singles champion, said on Eurosport.

"I did it [took late-career wildcards at the expense of young contenders] and I shouldn't have.

"It was the biggest mistake I made in my career."

Kyrgios defended Murray, who had hip surgery in 2018, with the Australian aiming criticism at Wilander.

"Shut up Mats, no-one cares," Kyrgios tweeted.

"Muzz, just know that how ever long you stay, we all appreciate and enjoy your tennis and banter.

"Also I've never watched a point of Mats Wilander."

Khachanov, the world number 16, responded to the Australian - who opted not to compete at the US Open and French Open due to health risks posed by the coronavirus pandemic - by calling on him to "show some respect".

"Nah I'm good dude," Kyrgios responded.

"Muzz and I respect each other, and if someone starts talking about one of mine then I'll come at them.

"I’m supposed to respect Mats? For what? Hitting a ball over the net? I don't give my respect for that."

"Bro it's your call," Khachanov replied.

"I really think you are a good lad and I don’t have any problem with you.

"But once you are sitting at home and writing different comments about players that makes me think who has the real problem."

Kyrgios responded by refencing his criticism of players for their actions during the coronavirus pandemic.

This included his denunciation of the ill-fated Adria Tour led by Novak Djokovic in June, which was cancelled because of a number of COVID-19 cases in Zadar in Croatia.

"So you think what the players did during this pandemic was smart?" Kyrgios said.

"I’d love to have an intellectual conversation with you but I’m not sure it would go further than how hard you could hit a ball.

"I’ve simply been holding people accountable."

The dispute continued with Khachanov saying "next time before talking about my intellect read at least a few books, instead or playing video games [the] whole day long".

This prompted Kyrgios to describe the Russian as an "absolute pelican", while adding that he had "been feeding the hungry, helping open up new facilities for kids to get active".

The dispute comes while Khachanov is still competing at the French Open.

The Russian is due to face Chile's Cristian Garin in the third round and the winner could face world number one Novak Djokovic in round four.