At the 1956MelbourneOlympic Games, he won a bronze medal in the pole vault, as he scored 4.50 m (Greek record at the time), on 26 November 1956. In order to attend the Melbourne event, Roubanis lost a semester of his studies at UCLA in the United States. He abandoned athletics in
1961. After studying political economics, he got his master's degree in local self-government. He had worked in the USA for 5 years as a management consultant, for a movie company. He had also set up an advertising company and a printing plant. In sports, he served as the President of the Panhellenic Association of Calisthenics and founded several other associations.