McEnroe: Serena would be ranked 'like 700' if she played against men

John McEnroe is loud and water is wet.

The tennis legend was his usual incendiary self in an interview with NPR's Lulu Garcia-Navarro, this time taking aim at a true living legend of the sport, Serena Williams, the owner of 23 Grand Slam victories.

"If she played the men's circuit she'd be (ranked) like 700 in the world," McEnroe said.

"That doesn't mean I don't think Serena is an incredible player," he added. "I do.

"On a given day, Serena could beat some players. I believe because she's so incredibly strong mentally that she could overcome some situations where players would choke, because she's been in it so many times, so many situations at Wimbledon, the U.S. Open, etcetera. But if she had to just play the circuit - the men's circuit - that would be an entirely different story."

The 700th-ranked man in singles on the ATP World Tour is currently Kenneth Raisma of Estonia, who's never appeared in a single Grand Slam event.