NASHVILLE, Tenn. - A year ago, when the guys in Def Leppard heard that Taylor Swift wanted to do an episode of the Country Music Television show "Crossroads" with them, they had just one question: Who's Taylor Swift?

"There's always a first time when you discover a band, whether it's the Beatles or Taylor Swift," Def Leppard singer Joe Elliott said.

"So we Googled her and iTuned her and listened to it all and said 'Wow.' And you look at how many records she's selling and how lovely and pretty she is and how exciting it is to be at that point in your career, because we were there once - before you were born," he added glancing over at the 18-year-old Swift at a recent press conference.

The show, a popular series on CMT that pairs country artists with pop and rock acts, will air 9 p.m. EST Friday.

Swift didn't have to Google the British rock band to find out about them. Her mom is a big fan.

"Before she met my dad she listened to them and all through while she was pregnant with me and when I was a little kid. It's just so cool to have that - my favorite songs are the same as my mom's favorite songs."

She said the band's hits like "Photograph" and "Pour Some Sugar on Me" were a blast to sing.

"It fits really well," she said. "The harmonies that they do on their songs are perfect for my range.

"There's a line in the song `When Love & Hate Collide,' the first line, and it says `You could have a change of heart, if you would only change your mind.' I've always been obsessed with that line and the melody of it, and I get to sing that line, and I'm so excited," said Swift, whose self-titled debut album has sold 3 million copies with hits such as "Our Song" and "Teardrops on My Guitar."

Her second album, "Fearless," comes out Tuesday. The first single, "Love Story," is No. 2 on the Billboard country chart (and No. 16 on the Billboard Hot 100).

This is Def Leppard's second collaboration with a country star this year. They teamed with Tim McGraw on the song "Nine Lives" from their latest album, "Songs from the Sparkle Lounge."

"Country is a state of mind rather than a place, I think," Elliott, 49, said in his thick English accent.