Nick Kyrgios overcame Stan Wawrinka at the Rogers Cup on Wednesday, but not before he stirred up social media when television microphones picked up the contorversial Australian trash talking his opponent.
"Kokkinakis banged your girlfriend. Sorry to tell you that, mate," Kyrgios was heard saying as he approached Wawrinka after the match in Montreal, referring to fellow Australian Thanasi Kokkinakis.
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Wawrinka went through a very public and messy divorce with his wife, Ilham, in April. Since the breakup, he is believed to be dating 19-year-old Croatian player Donna Vekic, presumably the subject of Kyrgios' slight.
Following the match, Sportsnet's Arash Madani asked Kyrgios what he was thinking when he made the comment and Kyrgios replied that he said it in the heat of the moment.
Wawrinka's coach, Magnus Norman, weighed in on the incident on Twitter.
That was really really low Nick Kyrgios. Hope for u that u have people around that will teach u a thing or 2 about life tonight. Very bad👎🏼
— Magnus Norman (@normansweden) August 13, 2015
But so did Kyrgios' brother Christos.
That's what happens when you get lippy. https://t.co/KPgzVSGYzP
— Christos Kyrgios (@xkyrgios) August 13, 2015
Wawrinka, the No. 3 seed at the ATP 1000 event, was trailing 4-0 in the third set when he retired from the match with a back injury. The Swiss two-time Grand Slam champion had taken the first set 7-6 (10-8) before dropping the second 6-3 to Kyrgios.
Kyrgios, 20, is one of tennis' rising stars. But he has also developed a reputation as one of the sport's most disliked personalities for his antics on and off the court.
Earlier this year, Kyrgios was criticized for his behavior during the Australian Open, which was followed by allegations of tanking during his Wimbledon loss to Richard Gasquet.
Kyrgios was also the subject of racially charged comments by Australian Olympic swimming legend Dawn Fraser.
Omnisport's Brandon Schlager contributed to this report.