Video | Nick Kyrgios sparks fury by sledging Stan Wawrinka over his girlfriend

Montreal: One of tennis’ most colourful and controversial characters Nick Kyrgios was branded ‘unacceptable’ after he was caught on camera sledging Stan Wawrinka during a match at the Montreal Masters, here on Thursday.

Kyrgios’ antics range from on-court outbursts at match officials and fans to being accused of giving up half-way through a match at Wimbledon earlier this year. (Photo: AP)

But this one might have topped the list for the Australian and arguably the greatest controversy. The incident came in the second set when Kyrgios and Wawrinka, the world No 5, were swapping ends. Kyrgios can clearly be heard saying: "Kokkinakis banged your girlfriend. Sorry to tell you that, mate.”

The harsh remark was made in reference to Thanasi Kokkinakis, Kyrgios’ Australian Davis Cup teammate and a close friend. French Open champion Wawrinka urged tennis authorities to take action against Kyrgios.

Wawrinka wrote on his Twitter account that the Australian's words were 'not only unacceptable but also beyond belief.' "There is no need for this kind of behaviour on or off the court and I hope the governing body of this sport does not stand for this," he said. (Photo: AP)

The fifth-ranked Wawrinka announced in April that he had separated from his wife, with whom he has a daughter. Kyrgios beat Wawrinka when the Swiss retired with a lower-back injury while trailing 4-0 in the third set. 

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