After former tennis star John McEnroe said Serena Williams would be ranked "like No. 700 in the world" if she played on the men’s circuit, Williams fired back.

In an interview with NPR on Sunday, McEnroe said Williams is the greatest female player in history, but she wouldn’t be one of the greatest ever.

Williams disagreed.

“Dear John,” Williams wrote in a statement on Twitter on Monday. “I adore and respect you but please please keep me out of your statements that are not factually based. I’ve never played anyone ranked ‘there’ no do I have time. Respect me and my privacy as I’m trying to have a baby. Good day sir.”

Even though his comments came off as an insult, McEnroe did not apologize for his comments on CBS This Morning on Tuesday.

“I don't want anything to go wrong with Serena because she's pregnant,” McEnroe said on CBS This Morning. “I don't want to upset her or whatever it was. I think she was doing it tongue-in-cheek as well, and I think that deep down we're talking about something, I can't even believe we're talking about it.”

McEnroe, 58, won seven Grand Slam titles during his career while Williams has, so far, won 23.