The blond, Los Angeles-born actress — who met A-Rod at the reopening of the Fontainebleau hotel in Miami Beach last November — was photographed at Friday's game, cheering on the Bronx Bombers at the new Yankee Stadium.
PHOTOS: More fun pics of Kate Hudson.
PHOTOS: Some very strange pics of Alex Rodriguez.
But the real action came later that night at Mustang Grill on Second Avenue. Our source said a bartender at the Southwestern joint at 85th Street "was asking patrons not to go in the back room around 1 a.m. because A-Rod and Kate Hudson were back there making out."
One staffer at the restaurant confirmed to Page Six the two were there celebrating the Yanks' win against the Minnesota Twins.
"Yes, they were here together," the server told us, although she did not witness any lip-lock herself.MORE: Go to NYPost.com for the full report.