Grammatikopoulos was born in Piraeus, May 16,1907. He started his football career at Aris Nikaia before transferring to Olympiakos whose nets he guarded from his debut on November 4, 1928 until 1944 - his last game being a friendly against Goudi.
He was considered one of the top keepers of the pre-WW II era and was capped 5 times by the Greek National team. His nickname during that time was "Zamora" after Ricardo Zamora, the top Spaniard goalkeeper of the same era. He was capped 5 times with the Greek National Team. He was part of 7 winning national championships with Olympiakos (1931,1932,1933,1934,1936,1937 και 1938), and an equal number of regional Piraeus championships (1929,1930,1931,1934,1937,1938 και 1940).
Grammatikopoulos saw action in World War II. After his playing career was over, he stayed on in football as a referee.