Nick Kyrgios was playing at the Toronto Open against Stanislas Wawrinka when he decided to drop a bomb to throw Wawrinka off his game. Kyrgios told Wawrinka that his teammate slept with Wawrinka's girlfriend.

Total dick move. You can hear it here:

He said:

“Kokkinakis banged your girlfriend sorry I just told you that mate.”

Wawrinka gone through a divorce earlier in the year, and is believed to be dating Croatian player Donna Vekic. Kyrgios made the remark when he was a set down. That stunt worked for him because Wawrinka retired from the game.

Wawrinka wasn't happy, and even blasted Kyrgios on Twitter after that.

And he wouldn't apologize for it.