Thomas Rhett Challenged by Danielle Bradbery 'Goodbye Summer' Duet

Thomas Rhett is featured on the new Danielle Bradbery single, "Goodbye Summer," a song he also co-wrote (along with Rhett Akins, Julian Bunetta and Jaren Johnston). But writing the song was much easier for Rhett than singing it alongside a vocal powerhouse like Bradbery.

"When I got in the studio my sole job on this song was trying to not sound terrible up next to how awesome Danielle's voice is," Rhett admits to PEOPLE. "I truly believe that Danielle is literally one of the best singers that I have ever heard in my entire existence. So when I got on that song, there was a part of me that was going, 'Do I sing this verse down in my register or do I try to copy Danielle's melody on the second verse?'"

The seasoned singer, who has had chart-topping hits like "Craving You" and "Marry Me," says singing "Goodbye Summer" was challenging, to say the least.

"[It was] one of the hardest times for me in the studio — trying to keep up with how amazing of a vocalist she is," Rhett reveals.

Bradbery previously sang with Rhett on "Playing With Fire," from Rhett's sophomore Tangled Up album. The alum of The Voice also toured with Rhett and Brett Eldredge, serving as the opening act on their co-headlining Suits & Boots Tour in 2015.

"I've known Danielle for so long [and I've gotten to] watch her grow into this amazing artist that she is today," Rhett says. "Her voice absolutely kills me and I'm just honored to be a very small part of this song."

"Goodbye Summer," which begins with, "He pulled into that parking lot with them out of state tags / I fell in love before he unpacked his bags," was originally written from the male perspective, before becoming a song that worked for male and female.

"Most of the time when you part ways from a summer fling you never know what's going to happen after that," Rhett explains. "That's the emotion of the song to me and that's where the idea stemmed from."

"It's a pulling into a beach town or a lake town or the middle of nowhere town and seeing that person," he continues. "You're like, 'Oh my gosh we're both single and we're immediately drawn to each other even though I'm from Tennessee and she's from Michigan. We're just going to spend the next like three months hanging out with each other.'"

Bradbery gravitated towards the lyric and the groove of "Goodbye Summer" from the beginning, but wasn't initially sure she wanted to include it on her recent I Don't Believe We've Met record.

"It was cool because without knowing what was going to happen to it, I still wanted to listen to it in my car or jam to it when I'm cleaning my house," says the 22-year-old. "It was such a fun song. It was so catchy and the story was really cool."

Download "Goodbye Summer" on iTunes.

Photo Credit: Getty images/Erika Goldring