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Justin Moore has nothing but praise for Miranda Lambert's contribution to his song "Old Habits." 

The country star tells when he first heard the work tape of the song he and his producer both agreed that it needed to be a duet -- and it needed Miranda. 

Moore says Lambert "knocked it out of the park," which he "knew she would."  He adds that he's grateful to her for taking the time to sing on his song, which he says is a sign of a true friend. 

Justin explains that "you really find out who our friends are when you call them and say, 'Sing this song with me,' and they just go, 'All right.'" 

"Old Habits" is on Moore's most recent album, Off The Beaten Path.

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