Is animosity toward rival fans generalizable across sporting and geographic contexts, and are such antisocial effects mitigated by multiple rivals? In Study 1, we replicate and extend a prior SMQ study by comparing animosity-related outcomes—prejudice, schadenfreude, disidentification, and behavioral discrimination—among fans ( N = 3,169) of professional teams in North America and the Indian Premier League (IPL). Results affirm significant contextual differences, with National Football League fans exhibiting higher animosity and IPL fans significantly lower animosity. In Study 2 ( N = 8,219), we introduce Rivalry Dispersion Theory , which is illustrated by findings that fans’ animosity toward the top rival is inversely associated with the number of perceived rivals and positively associated with variance in rivalry intensity. Importantly, fans’ identification and supportive behaviors are not strongly influenced by more rivals. Sport marketers can therefore consider mitigating the risk of antisocial effects by cultivating multiple rivalries without sacrificing fan support.