Williams said she experienced recreational mixed doubles, often played around her Florida home, but she sounded a more pessimistic note about customizing another competition to crowded tournaments.
"The plan is already so difficult," she said. "It sounds great, it sounds really exciting, but the big question is: Will it work? Will one of the tournaments take a chance on it? Maybe. We'll have to watch. It's about trying; who knows whether it will work or not? "
A person who is willing to try is Mark Ein, the long-term owner Washington Kastles, a World Team Tennis team who recently purchased the ATP-WTA tournament in Washington. One could not add a mixed double event in time for this year's tournament, which starts on July 29, but remains optimistic for future releases.
One quoted the thrill of Williams and Murray, as well as the mating of Venus Williams and Frances Tiafoe as a reason to invest in format.
"I think when you look at how fans react to mixed doubles, they love to see it," Ein said. "When you see the players playing it, you see true joy and love for the game. I think it translates to the fans. It only brings another, very special element to an event."
What's next for Murray unclear. Having suggested in January that he can retire after Wimbledon, he says he is now painless after another hip operation. He won the men's double title with Feliciano López at Queen's Club last month, but he lost in the second round at Wimbledon with Pierre-Hugues Herbert. On Wednesday, despite persistent issues, Murray did not provide a timeline for his plans, and not even commit to the United States Open in August.