"Every person that’s bought a ticket to come out here and heckle me ... it’s all going towards the Danielle Collins fund."

Tennis purists felt unsettled as Danielle Collins went right at a rowdy Australian crowd after taking out a hometown favourite in incredible scenes. But the exchange is actually healthy for the sport.

Count Novak Djokovic as being in Danielle Collins’ corner. He thinks her response to booing fans at the Australian Open was absolutely fine — which should come as no surprise, given the way Djokovic gets into back-and-forths with hecklers at his matches,