Sponsorship is one of the most used marketing tools today as well as it's one of the dominant sources of funding and survival of sports clubs. In addition to already mentioned, it's the strongest link between sporting events and economic activities. a sponsorship agreement (or contract) is a legal relationship between players, clubs, federations, leagues, and a sponsor. In this thesis, the main subject was sponsorship as a form of marketing communication in sports. It is explained throughout defining the concept of marketing and marketing in sport, defining (and explaining) elements of marketing communication, explaining the communication process as well as explaining the ways of communication in sports, defining the term sponsorship in sport, and showing the history of sponsorship in general with a focus on types and form of sponsorship in sports and it's positive and negative aspects. Secondary research presents examples in sports such as the Croatian Football Association, the Wimbledon Tennis Tournament, the World Cup, football clubs like Atletico Madrid, Juventus, Liverpool, and Barcelona as well as tennis players Roger Federer and Marin Cilic, football player Leo Messi and others that have served as examples for a better understanding of the theoretical part of this thesis. This paper presents a representative example from practice, a water polo club Jug, that was the main subject of primary research. the main goal of the research was to determine their use of sponsors in communication with different target publics along with the recognizability of sponsors with mentioned publics. proposal on how to improve particular marketing failures that would lead to better club marketing are given as well. In the future, repeated research may be conducted to determine if the club has taken advantage of the given suggestions and invested in sponsorship as a tool to communicate with its public.