Director Sarah Knight envisioned all female vocals for the "Diamonds are a Girl's Best Friend" soundtrack. However, very few women have recorded baseball songs. Nina Simone and Mabel Scott did, but those versions were beyond the film's budget. Knight researched and discovered a trove of old baseball ditties from the late 1800s-early 1900s. She sent them to musicians in all different genres and asked them to choose one to adapt to their specific style.