Protesters are preparing to demonstrate against the "extreme" views of tennis great Margaret Court at the Australian Open which begins in Melbourne next week.

Court, a 24-time grand slam singles title winner who is now senior pastor at the Victory Life Centre church in Perth, says the Federal Government's proposed gay marriage reforms would "legitimise what God calls abominable sexual practices".

Activists are calling for people to unfurl rainbow flags at the Margaret Court Arena and wear gay pride colours. Around 1,000 people are expected to take part.

Former Australian Medical Association president Kerryn Phelps is spearheading the criticism of Court's views.

Professor Phelps says Court's views go beyond a difference of opinion over gay marriage and are dangerous and hurtful.

"She's way past the foot fault now. I think she's so far out of court it's not funny," she said.

"Her views on homosexuality are so extreme that they really almost defy comment. I don't think that this is a matter of freedom of expression.

"In talking about, in the past, lesbianism 'destroying the game of tennis', she is inciting the bigots out there, giving them basically permission to say these sorts of things in the public arena, and it's very hurtful."

Professor Phelps also takes offence at Court's belief that homosexuality can be cured.

"There are a number of views that are particularly offensive. One that is of particular note is that she runs some kind of program in her so-called church where she tries to cure homosexuality," she said.

"Now you cannot cure something that's not a disease or a problem. The disease or the problem is homophobia. That's the thing that needs to be cured."

Freedom of speech

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Listen Duration: 3 minutes 1 second 3 m 1 s Kerryn Phelps talks to the ABC Download 1.4 MB

Earlier this week Court told Reuters that any protests would not stop her attending Open matches.

She said she was "sad" protesters might seek to use the tennis as a venue for expressing their views.

"Minority groups can have their views, [but] as soon as a Christian stands up it's not allowed," she said.

Court also said she stuck by her views on same-sex marriage but denied she was anti-gay.

"I actually love homosexual people," the 69-year-old said.

"I do not have anything against them. It's just my view and it's in the scriptures... the bible will always be the TV guide to my life.

"I believe marriage is something between a man and a woman."

Name recognition

But Professor Phelps says Court's name should be stripped from the Melbourne tennis arena which was named by Tennis Australia in honour of her achievements.

"The Australian Open is an iconic sporting event. It has international attention and for the name of somebody who has now associated themselves with some very extreme views that harm a lot of people, I don't think that that's appropriate for the name of that venue," she said.

"The really confusing thing here is that like any Australian, and like any sports fan, I can appreciate her sporting achievements.

"But I don't think that gives her licence to spread the kind of hateful comments that she is spreading. In fact, I think it's irresponsible for somebody to use their sporting fame to spread these kinds of views."

Tennis Australia says the arena was named in honour of Court's sporting achievements and her views are her own.

ABC/Reuters