World number five Stan Wawrinka responded strongly to Nick Kyrgios' sledge during their second-round clash at the Rogers Cup.
Stan Wawrinka has called on the ATP World Tour to respond to Nick Kyrgios' sledge at the Rogers Cup on Wednesday.
Kyrgios was heard to say: "[Thanasi] Kokkinakis banged your girlfriend. Sorry to tell you that, mate," in Wawrinka's direction during their Rogers Cup second-round clash in Montreal.
The Swiss later retired injured citing a back injury with Kyrgios leading 4-0 in the third set, with Wawrinka's coach Magnus Norman and former WTA world number one Victoria Azarenka among those to criticise the act.
And the recipient of the sledge also went on Twitter to express his views.
"So disappointing to see a fellow athlete and colleague be so disrespectful in a way I could never even imagine," Wawrinka posted.
"What was said I wouldn't say to my worst enemy. To stop [sic] so low is 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 and stands up for the integrity of this sport that we have worked so hard to build."
Kyrgios said in an on-court interview: "I thought he was getting a bit lippy at me so... it's just in the moment sort of stuff, but yeah, I don't really know, I just said it."