Pat Cash has claimed that some of the fans have been "out of control" in the early stages of the Australian Open.
Alexander Kudryavtsev labelled Australian fans "animals" during his loss to home favourite Marinko Matosevic in the first round, and Cash believes that the tournament's organisers need to take action against supporters who target players during matches.
"I talked to the authorities last year. My words were, if you invite international players out you've got to treat them with respect," Cash told Confidential.
"[On Monday] the security guys cracked down in the Marcos Baghdatis match, I was there watching, he's a mate of mine, and the crowds were out of control.
"The umpire came up and had a talk with them at the change of ends. I'm not saying don't cheer, but last year was out of control. Crowd behaviour has been the disappointing thing of the Australian Open for the last few years."
Ernests Gulbis was also heard telling supporters to "shut up" in his shock defeat to Australian teenager Thanasi Kokkinakis.