This study investigates the key determinants influencing student engagement and participation intention within university-based athletic clubs, focusing on the newly established Pickleball Club at the University of Finance - Marketing (UFM). Utilizing an extended Service Marketing Mix (7Ps) theoretical framework, a mixed-methods research design was conducted, combining qualitative scale adaptation (n=13) with a quantitative empirical survey of N=278 valid undergraduate respondents across UFM campuses. Data were analyzed using Cronbach’s Alpha, Exploratory Factor Analysis, and Multiple Linear Regression via SPSS 26.0. The empirical findings reveal that the 7Ps marketing mix collectively accounts for 60.6% of the variance in students' participation intention ("Adjusted " R^2=0.606,p<0.001). All seven hypotheses (H_1→H_7) were statistically supported, with Promotion (β=0.295) exerting the most significant positive impact, followed by Product (β=0.224), Physical Evidence (β=0.189), Price (β=0.178), People (β=0.151), Process (β=0.102), and Place (β=0.091). Based on the standardized regression hierarchy, actionable managerial implications are proposed, emphasizing short-form viral social media campaigns (TikTok/Reels), dual-track membership programming (recreational vs. competitive), co-branded merchandise, and streamlined online onboarding. This study provides a practical strategic model for optimizing student-led sports club operations in higher education institutions.