Call it the 21st century "Battle of the Sexes."

Some 42 years after Billie Jean King struck a chord for women by sweeping 55-year-old Bobby Riggs in a three-set sweep of a challenge tennis match, former Grand Slam champion and current NBC tennis analyst John McEnroe says he thinks he can beat reigning No. 1 women's player Serena Williams, USA Today Sports' For the Win is reporting.

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McEnroe is 56 years old and active in the champion's circuit. Williams is 34 and trying to complete the calendar Grand Slam with a win at the US Open to take place in a couple of weeks.

Talk show host Jimmy Kimmel asked McEnroe whom he thought would win a match between Serena and him.

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I believe that I could still take her," McEnroe said. "Fifteen years ago, Donald Trump ... made an offer, which I felt like was not enough, and I think he was humoring the two of us. Serena, she's got a lot to lose by losing to an old fart like myself. And I've got a lot to lose because if I lose to - God forbid - a woman, then I'm not allowed in any men's locker room for the next 15 years or possibly the end of my life. So that's part of why it's intriguing."

For the Win flashed back to a 2013 comment Williams made about current No. 2 player in the world Andy Murray, in which she said she'd lose 6-0, 6-0 and doubted she'd win a point. It polled "tennis insiders," who indicated that Williams might be able to beat a men's player ranked from No. 200-No. 300 or might not be able to beat a player in the top 1,500.

McEnroe once had said Serena might be able to beat the No. 500 player.

For the Win responded by picking McEnroe winning a best-of-three sets in three sets.

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