John Mayer feared his romance with Katy Perry would be wrecked if they worked together on a duet. The Daughters hitmaker recruited his leading lady for his latest album, Paradise Valley, and the superstar singers came together for a touching single called Who You Love. However, Mayer tells U.S. radio station z100 it was hard to convince him to team up with Perry as he was wary of collaborating with a girlfriend. Mayer explains, "I had this idea that just sat around for a while and I thought, 'Maybe I'll finish it some day' and I played it for (record producer) Don Was who was producing the record with me and he said, 'Get Katy to sing on it'. "Now, he could say that because he doesn't have to worry about all the hang ups that I'd have to worry about... She was an artist in the studio and partner out of the studio. It was really professional... There was a moment where she was like, 'Let me just go through it once', and the way I work is, 'Let's get this and that and that' and she was like, 'Let me try it my way.'" Besides the duet, Mayer insists he and Perry stay in their own lanes when it comes to their music careers, adding, "We were just fine before we met each other, that's what we say - 'You were fine before I met you, you don't need my advice,' and vice versa."