After criticism of her vocal opposition to same-sex marriage and calls to change the name of the court named after her at Melbourne Park, including from Navratilova, Court responded on Wednesday with a controversial interview.
Talking to a Christian radio station, the 24-time grand slam singles champion turned pastor said transgenderism was the work of the devil and compared a global plot to promote equal sexual rights to Hitler.
Her attitude has been universally condemned by all players willing to give their views, with Australian number one Sam Stosur suggesting some could choose to boycott Margaret Court Arena at next year's Australian Open.
In a letter addressed to the stadium and sent to Fairfax media in Australia, Navratilova, a prominent advocate for LGBT rights, said: "It is now clear exactly who Court is: an amazing tennis player, and a racist and a homophobe.
"Her vitriol is not just an opinion. She is actively trying to keep LGBT people from getting equal rights (note to Court: we are human beings, too). She is demonising trans kids and trans adults everywhere.
"And now, linking LGBT to Nazis, communists, the devil? This is not okay. This is in fact sick and it is dangerous. Kids will suffer more because of this continuous bashing and stigmatising of our LGBT community.
"How much blood will be on Margaret's hands because kids will continue to get beaten for being different? This is not okay. Too many will die by suicide because of this kind of intolerance, this kind of bashing and, yes, this kind of bullying. This is not okay."
Navratilova has called for the arena to be renamed in honour of Australia's seven-time grand slam singles champion Evonne Goolagong Cawley.
"We celebrate free speech, but that doesn't mean it is free of consequences - not punishment, but consequences," continued Navratilova, one of the game's greatest ever players.
"We should not be celebrating this kind of behaviour, this kind of philosophy. The platform people like Margaret Court use needs to be made smaller, not bigger.
"Which is why I think it's time to change your name. And I think the Evonne Goolagong Arena has a great ring to it. Now there is a person we can all celebrate. On every level."