“It’s one of the best songs written in the millennium,” confessed ‘Duets‘ celebrity mentor Robin Thicke just before taking the stage with hopeful Olivia Chisholm to perform Lady Antebellum‘s monster hit ‘Need You Now.’ With the competition down to only five hopefuls, was the country song the best choice for the two soft-voiced soul singers?

“I’ve always said that R&B and country are cousins,” said R&B singer John Legend. “It was fun.”

The sole full-time country mentor on the panel praised Chisholm’s ear for a great tune. “I loved the song choice,” said Sugarland‘s Jennifer Nettles. “It’s important to show your diversity on this show. I thought you did a wonderful job.”

Though Nettles and Legend were kind in their assessments, Kelly Clarkson had a more critical response for the performance of the Grammy Award-winning song. “I don’t know if it was the nerves because it was live,” acknowledged the singer, adding, “You were pretty pitchy.”

Even with her qualms about the performance, Clarkson did praise their decision to cover the Lady Antebellum tune. “I loved the song choice,” said Clarkson, who is currently climbing the charts with her first solo country single, ‘Mr. Know It All.’

‘Need You Now’ was the first single from Lady Antebellum’s sophomore album of the same name. The tune spent an impressive five weeks at No. 1 and became the best-selling country song of all time with more than five million digital downloads sold. The track also earned Lady Antebellum four Grammy Awards in 2011, including Record of the Year and Song of the Year.

Watch Robin Thicke and Olivia Chisholm Perform Lady A’s ‘Need You Now’

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