Keith Urban's song "The Fighter" was once a declaration of love for his estranged wife, Nicole Kidman. The track was featured on Urban's 2016 album, Ripcord, as a duet with Carrie Underwood. The following year, Urban released "The Fighter" as a single. As the song jumped on the charts, Urban opened up about how Kidman inspired the track. "It was just a very quick, quick song to write," he told The Boot in March 2017. "Because I literally thought about Nic and I and our relationship in the beginning, and some of the things we had said all went into that song.