Born in Kifisia, Sourpis was talented at the pole vault and volleyball, but chose to play football with Panathinaikos F.C.. He partnered Takis Papoulidis in the centre of defence in the 4-3-3 formation that coach Stjepan Bobek used at Panathinaikos. He played a total of 11 seasons for Panathinaikos, winning the Greek Alpha Ethniki six times, two Greek Football Cups, and helped the club reach the 1971 European Cup Final.