The incident took place during the first-set tie-break when Janowicz felt that a shot down the line from his opponent had bounced out, while Marija Cicak in the chair felt otherwise.
"What did I learn today? [That the] most important thing is you have to fight for every single ball till the end. I was losing already two sets to love and I kept on fighting," said Janowicz.
"You can't control your emotions all the time. Actually, I went nuts. I calmed down a little bit later on. Sometimes I have a problem with controlling my emotions, but I'm trying to work on this."
You can watch the 22-year-old's verbal tirade below.