He won his first major senior medal in 2007 at the European Indoor Athletics Championships, where he claimed the silver medal behind an Italian record-breaking Andrew Howe. On 2 June 2007 in Kalamata Tsatoumas jumped 8.66 metres, achieving a personal best and a Greek record for the event. The performance was the best in the world since Iván Pedroso leaped 8.70 m to win the gold medal at the 1995 World Championships. Tsatoumas ranks as the eighth best long jumper in history and holds the European record in the event at low altitude.