Over the weekend tennis legend John McEnroe told NPR that Serena Williams has earned the title of "greatest woman to play tennis," but added that he wouldn't put her in the category of greatest to ever play tennis.

Per ESPN,

"That doesn't mean I don't think Serena is an incredible player. I do. But the reality of what would happen on a given day is Serena could beat some players, I believe, because she is so incredibly strong mentally," McEnroe said.

"But if she had to just play the circuit -- the men's circuit -- that would be an entirely different story."

McEnroe went on to say that Serena would rank "like 700th" in the world if she played with the men, which naturally created a controversy. As a result, McEnroe appeared on CBS This Morning today, though he refused to apologize for his comments.

Check out Serena's response to McEnroe's remarks below, as well as McEnroe's interview on CBS This Morning.