CINCINNATI • Australia's Thanasi Kokkinakis, the subject of a controversial barb by pal Nick Kyrgios to Stan Wawrinka at Montreal, had some controversy of his own in qualifying for the Cincinnati Masters.

According to a Fox Sports report, Kokkinakis and American Ryan Harrison were involved in a heated match last Saturday, during which chair umpire Mohamed Lahyani twice had to separate the players.

Kokkinakis was agitated by a pair of call overrules Lahyani made on first-set break points in Harrison's favour, pressing his complaints to annoy Harrison.

Kokkinakis won the set and then confronted Harrison, who drew Kyrgios into his complaints by complaining about "new age little kids" and yelling sarcastically at the Australian: "Your crew is 'really cool'."

After the match, which Kokkinakis won 7-5, 3-6, 7-6 (7-2), Harrison said he thought the Australian was trying to start another row by not letting go of his hand during their post-match handshake.

"These kids, they have got to get under control," he said to the umpire in clear earshot of Kokkinakis.

The 23-year-old then spoke directly about the comment Kyrgios made to Wawrinka about his girlfriend having sexual relations with Kokkinakis.

"They are going to get hurt," Harrison said. "(Kokkinakis) is 19. If he wants to get into it, I will bury him. Wawrinka should have decked Kyrgios and I should deck that kid.

"I knew at 17, 18, 19 that there was just a line that you didn't cross," Harrison told Fox after the match. "And you certainly didn't try to seek after guys the way Thanasi sought after me for an altercation.

"These kids, if they keep thinking they can just come at people and instigate, someone is not going to be OK with that. The wrong guy on the wrong day, you never know what could have happened."

Kyrgios was fined the maximum US$10,000 (S$14,061) by the ATP and could face further sanctions, including possible suspension.

Kokkinakis has not been in trouble before and moved yesterday to distance himself from the Kyrgios controversy, slamming his friend for drawing him into it.

"I let him know. I made it pretty clear that he can't be doing that. If he's got a problem, he's got to say it in private," he told the Australian Associated Press.

Kokkinakis also revealed he has "cleared the air" with both Wawrinka and Wawrinka's girlfriend Donna Vekic, the WTA player he dated before she became involved with Wawrinka. AGENCE FRANCE-PRESSE

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