FC Porto the 1955–56 Primeira Divisão on head-to-head advantage over runners-up Benfica. Later that season, Porto beat Torreense to win its first Taça de Portugal and achieve its first double. As the Portuguese league winner, Porto made its debut in European competitions by qualifying for the 1956–57 European Cup. The club's first participation was short-lived, ending in the preliminary round with two defeats against Spanish champions Athletic Bilbao. A year later, Porto lifted its second Taça de Portugal by beating Benfica 1–0 in the final. The two clubs met again in the following season's final, but this time Benfica took the trophy
FC Porto in international football competitions name="1980/81"></ref><ref name="1982/83"></ref> In between, the club sailed into the 1981–82 Cup Winners' Cup quarter-finals, where they were beaten by the eventual runners-up Standard Liège.<ref name="1981/82"></ref> Porto lost the 1983 Portuguese Cup final to league champions Benfica, which allowed their participation in the 1983–84 Cup Winners' Cup as losing cup finalists. They eliminated Dinamo Zagreb, Rangers, and Shakhtar Donetsk to reach their first European semi-final.<ref name="1983/84"></ref> The competition draw paired Porto with the holders Aberdeen, managed by Alex Ferguson. Taking a 1–0 lead to Pittodrie, Porto resisted to the attacking pressure of their opponents. In the 76th minute, Vermelhinho scored the