The use of a sport celebrity as a message source is a popular way how to convince many consumers around the world to buy and use different services. In the last decades, we have seen that many sport celebrities in a serial way promote products and services of different companies at the same time or in a sequence. Therefore, there arises a question of message source credibility and trustfulness. The main objective of this research paper is to study the world famous Spanish tennis player’s appearance, Rafael Nadal, as a message source in different companies’ advertisements and the kind of image he creates. In this sense, a content analysis technique and a face-to-face survey technique (328 subjects) have been conducted to know what the consumers’ attitudes towards serial sport endorsers are.