Keith Urban got the inspiration for "The Fighter" when he heard Charlie Puth and Meghan Trainor's duet "Marvin Gaye" while riding in an Uber car in London.
He tells Billboard, "I thought I'd love to write a duet that is more of the girl asking something and the guy answering. I like that back and forward, a little bit like 'Baby, It's Cold Outside' or 'Paradise by the Dashboard Light' -- really more of a conversation."
Once he got to the studio, he and his co-writer busbee hammered out the rest of the song.
"I think we put down the chorus straight away with busbee filling in where the girl would sing. I still have a copy of him going (sings) 'What if I fall.' It's fantastic."