Video: Rascal Flatts Invade iHeartRadio Fest with Natasha Bedingfield

Rascal Flatts and Natasha Bedingfield perform at day 2 of the iHeartRadio Music Fesitval at the MGM Grand in Las Vegas.

Country music was well represented at the iHeartRadio Music Festival on Friday and Saturday (Sept. 23-24), with artists like Kenny Chesney and Carrie Underwood commanding the stage at the MGM Grand in Las Vegas. For their Saturday night performance, however, Rascal Flatts unleashed a secret, non-country weapon: Natasha Bedingfield, who joined the trio to perform their duet, "Easy."

"It's a song that's so emotionally wonderful and has an amazing story to it," Bedingfield told Billboard on the red carpet. "Easy" marks a departure for the Australian pop star, but she had no hesitations about exploring a new genre. "These guys, I love them, so when they approached me and were like, 'You should sing the song with us,' I was like, 'I'm there,'" she says.

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Meanwhile, the single release of "Easy" coincides with the end of Rascal Flatts' 2011 tour, which wrapped up last week in California. After performing hits like "Fast Cars and Freedom" and "Life is a Highway" at the first iHeartRadio fest, the trio plans taking in "a little downtime" and hopefully readying the follow-up to 2010's "Nothing Like This" for the spring, according to guitarist Joe Don Rooney.

"We're gonna finish a new album -- April 3rd of next year it'll be out -- and spend some time with the family back in Nashville, Tennessee," says Rooney. Bassist Jay DeMarcus joked, "I'm actually going to rehab. It's been a long summer."

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Watch the official video for "Easy," which premiered in July, below: