Drawing on three theories; uses and gratification, social identity, and reasoned action, this study investigates the moderating role of type of participation and the sport fanaticism between brand community identification (BCI) and oppositional brand loyalty (OBL). Moreover, it explores the influence of sports fanaticism on the type of participation. A convenience sample of 455 members from the online communities of the two most famous competing clubs in Egypt (Al-Ahly and Zamalek) was used ; the validity of the proposed model has been verified. To test the proposed hypotheses, partial least squares structural equation modeling (PLS-SEM) relying upon WarpPLS.7 was utilized. The findings indicated that sports fanaticism is more influential on posting engagement behavior than lurking engagement behavior. Moreover, BCI is a key enabler of OBL. Furthermore, the sport fanaticism does not moderate between BCI and OBL. Finally, BCI has stronger positive effect OBL among posters than lurkers in OBCs. Key academic and practical implications in sport industry are justified and clarified