It wasn’t the way the higher minds of American tennis drew it up when they set out on their mission to make mixed doubles a thing.They had their hearts set on a star-studded showdown, with singles champions like Carlos Alcaraz and Coco Gauff on one side of the net and Jannik Sinner and Naomi Osaka on the other.They got half of what they bargained for Wednesday night in the finals of this little tennis experiment in what happens when celebrity, singles stardom, a Grand Slam title and a $1 million payday are put into a beaker. Or maybe 40 percent, given six-time Grand Slam singles champion Iga Świątek played for a title with then-three-time singles finalist Casper Ruud.Their opponents, defending champs Sara Errani and Andrea Vavassori, who are actual doubles players, delivered a different sort of script. And maybe it wasn’t as sexy as a showdown of boldface names under the New York lights in a packed Arthur Ashe Stadium. But as sports experiments go, it ended up being one of the more captivating things that tennis has seen in a while.Here, in front of 24,000 fans making some big noise, tennis got an answer to one of its age-old questions: What happens when you put a team of doubles experts, who don’t get this kind of limelight all that often, against a couple of the best singles players of their generation?And when it was over, after two days of competition, four matches, seven dominant sets, one strange collapse, the most dramatic of finishes and too many exclamation-point volleys from the condor-like Vavassori to count, tennis had its answer.It was pretty emphatic. Doubles was victorious, with Errani and Vavassori beating Świątek and Ruud 6-3, 5-7, 10-6 in the final.In the deciding tiebreak, having frittered away an earlier chance to serve out the match, Vavassori cranked serves and crushed overheads with primal grunts. He jumped each time he and Errani grabbed a point and sprinted to slap her hand before the next serve.A point from the title, Errani hit an underarm second serve, a bizarre move she’d done on her way to the gold medal at the Paris Olympics. It didn’t work this time, but on the next point, Vavassori rolled a forehand at Świątek’s feet, and the dominant women’s player of the past three years couldn’t lift the ball over the net.The Italians dropped their rackets, and a moment later, Vavassori was lifting Errani into the air.