Tzanetoulakos was born on October 24, 1944. A local Piraeus lad from Hadjikyriakio, Tzanetoulakos started his career as a substitute for Paraschos Avgitidis on Olympiakos. He first appeared in the Alpha Ethniki in the 1965 season playing in 4 games for the red-and-whites. In the summer of that year he was sent to Proodeftiki as part of the deal that brought Yiannis Fronimidis to Olympiakos.
At Proodeftiki, Tzanetoulakos got some playing time as a regular and quickly evolved into one of the better keepers in Greece of the late 1960s. In 1973, he transferred to Panachaiki where he played until the 1975 season.