Born in Alcântara (Lisbon), Germano started playing with local Atlético Clube de Portugal, spending seven of his nine seasons in the top division. In the 1960 summer he moved to neighbouring S.L. Benfica, where he remained for the following six years, being a leading defensive unit of the sides that won four national championships and two European Cups (against FC Barcelona and Real Madrid); in the latter competition's 1964–65 edition, he was placed in goal following his teammate's Alberto da Costa Pereira injury in the final against Inter Milan, and kept a clean sheet for more than 30 minutes, albeit in a 0–1 loss.
Germano played 24 times with Portugal, during 13 years. He was part of the squad that appeared at the 1966 FIFA World Cup but, after a subpar performance in the second game against Bulgaria, was benched for the rest of the tournament, which ended with a third-place conquest.