Boris Becker played hard at Nick Kyrgios on Tuesday. The 52-year-old German denounces the Australian number forty in the world for openly criticizing Alexander Zverev.

"I don't like rats. Anyone who challenges their fellow athletes is not a friend of mine. Look in the mirror if you think you are better than us," Becker, who has a good relationship with fellow countryman Zverev, writes on Twitter.

Kyrgios isn't the only tennis player to comment on 23-year-old Zverev after a video surfaced Monday showing the global number seven attending a party by German designer Philipp Plein. A few days earlier, Zverev had said that he would be quarantined for two weeks because he participated in the Adria Tour.

At the much-discussed Novak Djokovic tournament, the corona measures were not taken seriously and several tennis players became infected, including Djokovic himself. Zverev tested negative, but said he regretted his participation.

Kyrgios already spoke of the behavior of his colleagues during and shortly after the Adria Tour and lashed out again after the images of Zverev at the party were leaked. "You have your management write a message with excuses and say you are going to be quarantined. Then have the decency to actually do it," he said on Instagram.

Alexander Zverev and Nick Kyrgios after Acapulco's ATP tournament in 2019. (Photo: Pro Shots)

"Why are you talking about tennis?"

Kygios, 25, quickly responded to Becker's criticism on Twitter. "To be clear, Boris, I'm not trying to throw anyone under the bus. We're in a global pandemic, and if someone does something as insane as Alex did, I'll call him to order. Simple."

The quarrel between three-time Wimbledon winner Becker and Kyrgios continued for a while. "COVID-19 is terrible. It has cost a lot of human lives. We must therefore stick to the measures, but I still don't like rats," Becker wrote.

"Am I a rat because I point out his responsibilities to someone?" Replied Kyrgios. "That's a weird way of thinking, champion." Becker then said he would like to see Kyrgios, who has often been discredited in recent years, live up to his potential and win a Grand Slam tournament. "He would be a great role model for the youth," said Becker with some cynicism.

"Why are you talking about tennis now?" Said Kyrgios. "What about the man you are defending? Will he come up with an explanation instead of a standard apology from his management?"

The tennis season will resume next month, although there is increasing discussion about this, partly due to the corona infections among players.

Video

Sascha Zverev six days ago after Adria Tour coronavirus cluster: “I deeply apologize to anyone that I have put at risk ... I will proceed to follow self-isolating guidelines ... stay safe 🙏.” Sascha Zverev four hours ago:

AvatarAvatar Author BenRothenberg Time of places 18: 27 - 28 June 2020