The 24-year-old "Legends" singer turned heads in custom-made Brandon Maxwell sequin black pants and matching crop top, which she revealed to ET's Nancy O'Dell were created while she visited the designer last month.
"I was in New York, probably a month ago, and visited my friend Brandon Maxwell and he was like, 'Can you try on those pants?' And I was like, 'Oh, the black sequin pants?'" the blonde bombshell explained. "And I tried them on and he got the roll of fabric and made this top for me. And then my after-performance outfit is another version of this that he made on my body."
"I feel like I can't properly breathe. I'm totally sucking it in. 100 percent," Ballerini joked, before adding that the outfits are "just the coolest thing ever! It's like another form of art. I was just fascinated. He's amazing. It was fun, it was really fun."
Maxwell is also a big fan of Ballerini, telling ET: "I loved Kelsea from the moment I heard her voice. I made my Fall 2017 Collection to the soundtrack of her first album and working with her was a dream. Her soul is as beautiful as the voice and I enjoyed every second."
Ballerini's stylist, Krista Roser, also tells ET exclusively that she and Maxwell created the singer's look in his office.
"Working with Brandon was such an honor,"Roser shares. "I have followed him and his talents since he started as a stylist. His designs are modern and classic, so working with him with Kelsea was such a natural collaboration. We literally just started creating this dream look on Kelsea right in his office."
Fashion aside, Ballerini -- who later took the stage to perform "I Hate Love Songs" -- couldn't help but gush about her husband, Morgan Evans, and life as a newlywed. The two were photographed on the red carpet showing some PDA.
"Awesome," Ballerini marveled about being a wife. "He's here! He has a Top 15 song, he's somewhere looking hot. Yeah, he's amazing and just to be able to both do our own thing and celebrate each other, and then come together and celebrate country music, it's awesome. It's epic."
"There's an extra level of comfort you get and you just know [that] no matter what that person has your back and vice versa," she expressed. "And that's just one of those things that won't change. It's really comforting."
Meanwhile, the singer was also excited to kick off CMA Fest, which she said "is one of my favorites."
"It's all about the fans you know," she expressed. "The fans are the whole audience and they vote for the awards and it's just a really, it's kind of the party show. Everyone has a good time and I'm really excited."
See more amazing looks from the CMT Awards red carpet, in ET's gallery below.