Miranda Lambert admitted she was a little nervous to perform her new song "Vice" for the first time. She surely wasn't expecting what happened the moment she started singing.

The singer introduced the single to fans in Cleveland on Thursday (July 28). After talking about how it'd been one year since she released a new single, she started singing for fans at the Blossom Music Center. Surprisingly, they started singing, too. Much of her Keeper of the Flame Tour crowd already knew the words to the lead single from her sixth studio album, the follow-up to Platinum.

There was one first-timer moment during the performance, but by the midway point she looked like she was singing just another Miranda Lambert hit, with more swagger and confidence than hesitation and nervousness. Cleveland.com reports there were over 12,000 fans in attendance to see her show with Kip Moore and Brothers Osborne. For many, "Vice" was surely a highlight.

The song debuted at No. 1 on iTunes, after which Lambert got emotional on Instagram and talked for the first time about her past year, calling it one of “heartache and healing.”

Accepting the flaws and celebrating the smiles. Finding peace in dark places … having some moments alone with me. Facing fears and feelings… All of them. I got to know my guitars…became friends with a pencil and paper … Used melodies to lead me places I had never been…. Made music with my friends. Because music is medicine. This means the world to me. Thank you for joining me on this journey.”

The Keeper of the Flame Tour continues in Illinois and Nebraska this weekend, with dates through mid-September. Lambert has not announced complete plans for her sixth studio album quite yet. It's not clear if she'll release it to fans in 2016 or if the project will wait until early next year.

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