1980–81 S.L. Benfica season the club. Benfica's league campaign started with seven consecutive wins, before a first loss with Porto in the Clássico. A few days later, Benfica wins their first Supertaça de Portugal. In the Cup Winners' Cup, Benfica eliminated Altay, Dinamo Zagreb and Malmö in the first three rounds. In late November, Benfica draws with Sporting and three weeks later, with Vitória de Setúbal, lapping the first half in first place with a three-point lead. In the following weeks, Benfica won three more matches before losing another point in a draw with Penafiel, which cut his lead to two points. They reacted
FC Porto in international football competitions losing the 1964 Portuguese Cup final against champions Benfica. Porto progressed from the first round of a European competition for the first time, after a 4–0 aggregate victory over French Cup winners Lyon, but fell in the next round to 1860 Munich.<ref name="1964/65"></ref> At the end of that season, Porto finished runners-up to Benfica in the league and qualified for the following season's Fairs Cup. The club's performance was similar to that of the previous campaign: a first-round elimination of a French team (Stade Français) followed by a second-round loss to a German team (Hannover 96),<ref name="1965/66"></ref> which included a