Pat Cash has urged Nick Kyrgios to not change his attitude on the court in the face of what he believes to be unfair criticism.

Kyrgios received a fine after the first round of the Australian Open for an angry outburst, but Cash believes that the 19-year-old's energetic demeanour on court is crucial to his game.

"It's him, I've got to be honest and say I've been disappointed with the higher people in Tennis Australia criticising Nick openly. I don't think that's right," Cash responded when asked about his compatriot's personality.

"He's got the personality, that's why he plays that way. That's what you want, the X-factor and that brashness. You don't want to take that away.

"He may have to learn when it becomes negative and when it's not, but it's part of him. That's why he's a good player and that's why he's a good talent."

Kyrgios will meet Malek Jaziri in the third round on Friday.