Why rising Aussie tennis stars are 'losing the plot'?

After Nick Kyrgios, another Aussie involved in verbal volley as tempers flare in Ohio

Bernard Tomic, Nick Kyrgios and Thanasi Kokkinakis have been making headlines for all the wrong reasons, leaving media to ask: "Are the trio of stars losing the plot because they are young, restless, stupid or victims of their own poor judgement?"

Australian teenager Thanasi Kokkinakis and his American opponent Ryan Harrison will escape disciplinary action following their verbal spat the Cincinnati Masters, the Association of Tennis Professionals said on Sunday.

Kokkinakis and Harrison were involved in at least two heated exchanges in a qualifying match in Ohio on Saturday, with video of the verbal encounters going viral on the internet.

Their run-ins came just three days after another Australian, Nick Kyrgios, brought attention to Kokkinakis with a comment at the Rogers Cup in Montreal.

Kyrgios muttered to Swiss opponent Stanislas Wawrinka that Kokkinakis had sexual relations with 'your girlfriend'.

He was referring to women’s pro Donna Vecik, who has been linked to Wawrinka and Kokkinakis.

Kyrgios was fined the maximum $10,000 by the ATP and could face further sanctions, including possible suspension.

But Kokkinakis escaped a similar fate for what happened on Saturday, with an ATP spokesperson telling Reuters that no action would be taken.

Video shows Kokkinakis and Harrison exchanging words after the first set.

Later, as they met at the net for the traditional handshake at the end of their close match, which Kokkinakis, 19, won in a third set tiebreak, video shows a further verbal exchange that prompted umpire Mohamed Lahyani to quickly climb down from his chair and enter the court to intervene.

Another official also arrived to help keep a lid on things.

After they separated and returned to their respective chairs to grab their possessions, Harrison said loudly: “These kids, they’ve got to get under control. They're going to get hurt.”

Kokkinakis seems to protest that he has done nothing wrong.