S.L. Benfica Sporting. Followed in Europe, Africa and the Americas, any match between both teams is known as "dérbi de Lisboa" ("Lisbon derby"), "dérbi eterno" ("eternal derby"), "dérbi da Segunda Circular", "dérbi dos dérbis" ("derby of the derbies") – the most important football derby in Portugal. The rivalry between Benfica and FC Porto, which started with a friendly match on 28 April 1912, comes about as Lisbon and Porto are the largest Portuguese cities, respectively. Benfica and Porto are currently the two most decorated clubs in Portuguese football, with the former historically being the most decorated team overall. Any match between the
1970–71 S.L. Benfica season put Sporting and Benfica level on points. Benfica closed March with an away win over Leixões, with Porto losing and dropping out of race. This left Benfica and Sporting with a three–point lead and three match-days to go. On 4 April, Benfica beat Vitória de Setúbal at home and for the first time headed the league isolated, with a two-point lead. Sporting had lost with Porto. Three weeks later, Benfica confirmed their league title with an away win over Varzim. It was their 18th league title. They finished the Primeira Divisão with a 5–1 victory over Académica, ending the campaign