Roger Federer and Serena Williams are set to kick off 2019 in an unprecedented, once-in-a-lifetime way. 

The tennis legends will meet on the court for the first time in a mixed doubles match Tuesday between Switzerland and the U.S. at the Hopman Cup in Perth, Australia. The hotly anticipated event is already being billed as “Federer vs. Williams,” though they’ll be joined by Swiss player Belinda Bencic and American Frances Tiafoe. 

In an interview with Agence France-Presse published Monday, Federer said he was hopeful his fans from around the world would tune in “because it’s going to be one time and probably never again.” 

“We’re both fierce competitors, and we always want to win,” he added. “She is one of the biggest champions in our sport ever, men and women combined, so it is great to be playing against her.” 

Williams echoed those sentiments, calling the match “a dream come true” even as she expressed relief that she wasn’t facing Federer in a singles match. 

“I have been looking forward to it,” she told The New York Times. “I was like, ‘Oh, my God, this is so cool.’ So it’s just something that, as a player, is something that you would dream of, to play Roger Federer.”

As of Monday afternoon, the match had generated enormous buzz among tennis enthusiasts ― which isn’t surprising given that Federer and Williams have collectively won 43 Grand Slam titles. Some fans and media outlets were likening the match to 1973′s “Battle of the Sexes,” when 39-time Grand Slam champion Billie Jean King beat former men’s world No. 1 Bobby Riggs in straight sets. 

Williams’ coach, Patrick Mouratoglou, appeared to shrug off the hype. His focus, he told The New York Times, was on the solo matches “because my goal is that she wins the Australian Open,” which begins Jan. 14.