LOS ANGELES • Tennis legend John McEnroe says that, while he has great respect for Serena Williams as the best of her gender, the 23-time Grand Slam winner would be the 700th-ranked player in the men's game.
Speaking as part of a tour to promote his new book "But Seriously" on Sunday, McEnroe said he would place Williams "like 700 in the world" on the men's circuit.
"Best female player ever - no question. If she had to just play the circuit - the men's circuit - that would be an entirely different story," McEnroe told American broadcaster National Public Radio.
The seven-time Grand Slam winner said the best thing Williams would have going for her on the men's tour would be her mental toughness.
"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," said McEnroe.
He said her rivals would crack under pressure. "She could overcome some situations where players would choke because she's been in it so many times, so many situations at Wimbledon, the US Open, etc," he said.
Williams became the oldest woman to win a Grand Slam title when she claimed the 2017 Australian Open title at the age of 35.
The Los Angeles native has 23 Grand Slam singles crowns and 14 doubles titles in Grand Slams.
The ATP Tour rankings only go to the top 500 and Andy Murray is the current top-ranked player while Temur Ismailov of Uzbekistan holds down the 500th spot.
Williams, who is six months pregnant, was asked about the possibility of an exhibition match against Scot Murray during an appearance on US TV show Late Night with David Letterman four years ago.
"For me, men's tennis and women's tennis are completely, almost, two separate sports," she said.
"If I were to play Andy Murray, I would lose 6-0, 6-0 in five to six minutes, maybe 10 minutes. It's a completely different sport.
"The men are a lot faster and they serve harder, they hit harder, it's just a different game. I only want to play girls, because I don't want to be embarrassed."
McEnroe, 58, told US TV host Jimmy Kimmel two years ago that he believed he could still beat Williams.
AGENCE FRANCE-PRESSE, WASHINGTON POST