"Watch out for him," the Oscar winner and recent American Idol mentor said of the folk-pop specialist, who in a seeming upset over Danny Gokey won passage into next week's finale alongside Lambert after wowing with his acoustic interpretation of Kanye West's "Heartless."
"Kris really sort of swooned me," Foxx said on the Ellen DeGeneres Show in an appearance airing Monday. "Ya know, I'm a macho man, but he was singing and I was like, oh my goodness.
"I was like, 'Dude, you had me floating for a minute.' So I told him I would really, really love to do a record with him because he's sort of understated."
Foxx also said that he reminded the five contestants he worked with for Rat Pack Night that they should always take the time to pose for pictures with their fans.
"Take that picture," Foxx advised. "U2 takes pictures, the Rolling Stones take pictures. I got a picture with Mick Jagger and he didn't have to take time out of his thing but he did it...I look at that and go, wow, somebody big like that took the time out.
"I told all of them—especially Adam because I think Adam has this thing. He has to be ready for that ride because if he gets the right record, he is going to go stratosphere."
But what about next Wednesday?
"Adam is gonna win, I believe," Foxx said.