Benfica's youth ranks, he made his debut with the first team on 30 December 1983 (aged 17) after being brought on as a substitute by manager Sven-Göran Eriksson in a 4–0 home win over G.D. Chaves in the Taça de Portugal.
[1] His only Primeira Liga goal came in a 2–2 away draw against S.C. Braga, and he went on to have a somewhat important role in the Lisbon club for seven seasons.
[1] Samuel started in the final of the 1989–90 European Cup, a 1–0 loss against AC Milan, pitching in at left-back on the occasion.
[2][1] His last game was a 1–0 victory at Louletano D.C. on 29 November 1992, and he went on to represent Boavista FC – he returned to Benfica for the 1992–93 campaign, but was released at its closure – Vitória de Guimarães, F.C.
[3] Samuel's son, Domingos, represented Portugal at youth level[4] and played professionally for several clubs, starting out at West Ham United.