In 1964 Haydar Shonjani became the first swimmer from Iran to compete at the Olympics when he was selected as part of their delegation at the Tokyo Games. Shonjani swam in the 100 metres freestyle but finished last in his heat and was eliminated. Staying in the pool, he then focused on water polo, with him being part of the Iranian team that won gold at the 1974 Asian Games in Tehran. The following year he also competed at the World Aquatics Championships in Colombia before making his return to the Olympics for the 1976 Montréal Games. Shonjani played in all of Iran’s matches in both the group stage and the classification round.