The main objectives of the present study are (a) to examine soccer players' use of music to psychologically prepare for performance and (b) to present a grounded theory to illuminate this phenomenon. Thirty-four academy soccer players (Mage = 17.9 years, SD = 1.6 years) were selected from a U.K. Premier League soccer club. Individual- and group-based questionnaires, reflective journals, and interviews were administered. Corbin and Strauss's (2015) variant of grounded theory was adopted, which is underpinned by pragmatism and symbolic interactionism. Data were analyzed using open, axial, and selective coding. Moreover, the data were continually compared with previous literature to verify methodological coherence, propose new methods, and develop a substantive grounded theory model. The findings document the use of music as a stimulant and regulator of emotion prior to performance, as well as its propensity to develop shared meanings and contribute to a sense of group identity. The analysis brought to light personal-, group-, and task-related factors that moderate the influence of music on the psychological state of young soccer players. A unique finding to emerge was the degree to which the music preferences of senior players were readily accepted by junior players. The present study provides evidence of the role that naturalistic research can play in fathoming and harnessing the emotive and encultured power of music within the social spheres of elite team sports. All emergent concepts can be used as a template to guide soccer players and practitioners in the use of music and to frame future research efforts.