Nick Kyrgios has thrown a cheeky barb in the direction of Stefanos Tsitsipas and his mother, Julia Apostoli, after he was accused of playing 'dirty tennis' against the Greek star at Wimbledon.
The pair have a somewhat tumultuous relationship that has played out over the years, but it came to a head in the Wimbledon third round and culminated in the two exchanging insults in their post-match press conferences.
Fined a combined $20,600 between them for audible obscenities and an incident in which Tsitsipas hit a ball towards the crowd, Tsitsipas accused Kyrgios of being a 'bully', with an 'evil side'.
This prompted Kyrgios to label his rival 'soft' in response, a comment which attracted significant criticism at the time.
It seems the feud won't soon be forgotten, with Apostoli giving an interview to the Greek City Times discussing the rivalry.
Apostoli said her son was 'confused' by Kyrgios' style and demeanour on court.
“The only person who confuses Stefanos is Nick Kyrgios,” she said.
“He is the only one who brings him out of himself.
“In the Wimbledon match, Kyrgios decided to ignore the general rules of sports. The match became very strange and nervous because he was playing ‘dirty’ tennis.
“Stefanos doesn’t play like that. He completely lost his temper due to the behaviour of his opponent and lost the match without being any worse on the court.”
The comments didn't escape Kyrgios' attention, with the Australian star taking to his Instagram story with a highlight from his win over Tsitsipas.
He posted a clip of him hitting a drop shot winner, captioning it 'dirty tennis', clearly alluding to the comments from Apostoli.
Nick Kyrgios and Stefanos Tsitsipas' love-hate tennis relationship
Tsitsipas conceded he lost his temper during their clash at Wimbledon this year, but said after the match that Kyrgios' constant complaining and outbursts needed to cease.
Stopping short of an all-out personal attack, Tsitsipas said Kyrgios brought many good things to the sport, but they were beginning to be overshadowed by the accompanying theatrics.
“You get tired of it. The constant talking. The constant complaining. We’re there to play tennis, not to have dialogues,” Tsitsipas said at Wimbledon.
“It’s constant bullying, that’s what he does. He bullies the opponents. He was probably a bully at school himself. I don’t like bullies. I don’t like people that put other people down.
“He has some good traits in his character, as well. But … he also has a very evil side to him, which if it’s exposed, it can really do a lot of harm and bad to the people around him.
“There is no other player that does this. There is no other player that is so upset and frustrated all the time with something.
"I really hope all us players can come up with something and make this a cleaner version of our sport, have this kind of behaviour not tolerated.”
Kyrgios laughed off Tsitsipas' claims before sarcastically saying he'd be upset as well if he'd lost to the same opponent four times in as many matches.
"I don't know what to say. I'm not sure how I bullied him," Kyrgios said.
"He was the one hitting balls at me, he was the one that hit a spectator, he was the one that smacked it out of the stadium.
"I didn't do anything. Apart from me just going back and forth to the umpire for a bit, I did nothing towards Stefanos today that was disrespectful, I don't think. I was not drilling him with balls."
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