John McEnroe's opinion is that she would not be ranked very high on the men's pro tennis circuit. "This is not something that has been earth shattering, that I feel there's a difference in the level of the women and the men".
Kate Dale, from Sport England's This Girl Can campaign told The Debrief, 'If a woman who's been at the top of her game for over 15 years can be called out like this then what hope is there for the rest of us?
The world number 701 Dmitry Tursunov, a 34-year-old from Russian Federation who was once ranked as high as 20 in the world, has supported McEnroe's claims by adding that he believes he would beat Williams. I didn't realise it would create something like this but maybe it's better if it hadn't been said because I have a lot of respect for Serena.
She took to her Twitter account to write, "Dear John, I adore and respect you but please please keep me out of your statements that are not factually based".
"I prefer the words 'one of the greatest athletes of all time", she said at a post-Wimbledon press conference. I don't want to upset her or whatever it was.
Compared to her friend Beyoncé, Williams has had a rather public pregnancy, debuting her baby bump at the 2017 Met Gala back in May. "I saw a person in her, for whom I wanted to become better", Alexis said. How am I going to play the Australian Open?'
I don't know about you, but here at LeBuzz Towers we're pretty exhausted of all of this conjecture.
"It would be a similar argument to who would run faster, the fastest woman or the fastest man?"
It's worth noting she has 23 Grand Slam wins - that's a record for both women and men in Open Era history.