As a player Popovic's usual position was centre-back. Starting in 1989 at Sydney United he went on to play for Sanfrecce Hiroshima of Japan and Premier League side Crystal Palace, among other clubs. He appeared with the Australian national team at the 2006 FIFA World Cup, where he played against reigning World Champions Brazil.
Popovic started his managing career in 2008 with Sydney FC. After a brief stint as assistant at Crystal Palace he was chosen as the inaugural manager of Western Sydney Wanderers at the start of the 2012–13 season.