Yugoslavia's Partizan Water Polo Club produced many great water polo players over the years including: Hall of Famers Zoran Jankovic, Ciro Kovacic, Igor Milanovic, and Mirko Sandie. In 1975, at the age of eleven, Alexandar Sostar joined the club. In his 16 years with the club and another 10 years with four other clubs, he developed into one of the world's greatest water polo goal keepers of all time. At 6 feet 5 inches tall weighing 225 pounds, he kept the opposing team from scoring goals, deflecting many shots on goal. At the 1988 Seoul Olympics, Yugoslavia won the gold medal, losing only one game in the tournament, and defeating the USA in the final round.
Sostar was known as a fierce competitor, quick with his hands and reflexes and never willing to give his opponents an opportunity to score. Prevented from playing in the 1992 Barcelona Olympics due to United Nations sanctions, he competed again in 1996 Atlanta as Serbia and Montenegro finishing in 8th place. At the 2000 Sydney Olympic Games, his team was back on the podium, winning the bronze medal behind Hungry and Russia. He also won gold and bronze medals at the 1991 and 2000 World Championships respectively and competed in five European Championships, winning two gold medals and three silver medals.
As a goal keeper, Sostar was dominant for most of his 20 year career. Since his retirement from the game he has been the President of Serbia and Montenegro Water Polo Federation, Director of Sport for the Serbian Government,Assistant to the Minister of Sports for the Republic of Serbia and President of Serbian Sports Association. In 2001, he was declared "Athlete and Sportsman of the Year" for Yugoslavia.