The purpose of the current study was to examine the effect of the services provided by the fans to the club on the participation and success of Sepahan and Tractor professional clubs. The present research is an applied study that employs causal-comparative for its purposes. The required information was collected using field methods and questionnaires. The statistical population of this study includes all fans of Sepahan and Tractor clubs, the total number of which is deemed unlimited. According to the characteristics of the statistical population, the requirements of the volume-based stratified sampling, and the recommendations of the Morgan Table, a total of 384 fans from Sepahan and Tractor clubs were selected as the research sample (i.e., 247 questionnaires from Sepahan fans and 137 questionnaires from Tractor fans). Furthermore, a researcher-made questionnaire based on a literature review was used to measure the research variables. The Cronbach's alpha of above 0.7 indicated the internal consistency of the questionnaire. The distribution of variables was evaluated using Kolmogorov and Smirnov tests, all of which were abnormal. The data obtained from the questionnaires were analyzed using one-sample sign and Mann–Whitney U tests, the findings from which indicated that the fans of Sepahan and Tractor clubs provided a higher-than-expected level of services to their respective teams. Moreover, the results revealed a significant difference between the level of services provided by the fans of Sepahan and Tractor Clubs. The final position of the clubs in the four seasons of 2011/2012, 2012/2013, 2013/2014, and 2014/2015, in which both clubs enjoyed high-position finishes, indicates that the involvement and participation of passionate and loyal fans have improved the team (win in most games, exhibiting free-flowing game.
