The seven time grand slam winner John McEnroe says he regrets saying Serena Williams would be ranked 700th in the world if she had to play on the men's tennis circuit.
McEnroe says it would have been better not to have said it and was suprised by the controversy his comments ignited.
"It would have been better not to have said it. I didn't realize it would create something like this," he said.
"It would have been easier to leave it. Look, she's a great player and it's apples and oranges."
McEnroe has previously said that Williams, a record 23-times grand slam champion in the professional era, was the best female player ever.
But McEnroe, a seven-times grand slam winner did not retract his earlier statement about where Williams would rank if she competed against men.
"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," he said.
Williams, who has taken a break from tennis to have her first child, due in late August, responded testily to McEnroe on Twitter after his initial comments.
"Dear John, I adore and respect you but please please keep me out of your statements that are not factually based," she wrote.
"I've never played anyone ranked 'there' nor do I have time. Respect me and my privacy as I'm trying to have a baby. Good day sir."
McEnroe said that Williams, a fellow American, has been great for U.S. tennis, which has not seen a single American male player win a major tournament since 2003.
"Obviously if it wasn't for Serena, American tennis would even be in a lot deeper trouble," he said.