Team identification is among the most widely studied concepts in sport fan behavior; however, with few exceptions, scholars have focused on the healthy and stable attachments fans form with their favorite team(s). In this study, we argue that this is not always the case. Drawing on literature from social psychology on a construct referred to as collective narcissism, we illustrate how sport fans’ identification with their favorite team(s) may take a collectively narcissistic form that results in markedly different outcomes compared with the generally positive team identification that has been so vigorously studied in the literature. Specifically, we explore the moderating role of collective narcissism on the relationship between team identification and both dysfunctional fandom and aggression. In doing so, we illustrate the importance of measuring collective narcissism alongside team identification in future studies to provide a more complete understanding of fan dysfunction.