After the pair palled around with Fergie in the chilly outdoor backstage area at the Nokia Theatre in Los Angeles, "A-Rod gave Kate a big squeeze to keep her warm," says a source, "and a sweet smooch."
Hudson was, "beaming, glowing actually," adds the source.
Hudson, along with Nicole Kidman, who both star in the upcoming Nine with Fergie, introduced the singer-actress's performance with the Black Eyed Peas, while Rodriguez introduced Jay-Z and Alicia Keys, who sang their hit, "Empire State Of Mind."
Hudson, in a barely-there silver dress, ignited giggles from the crowd when she repeatedly adjusted her plunging neck line. But backstage, she "didn't look uncomfortable at all in the outfit," says the source.