S.L. Benfica 2015, Benfica reported to have 246,401 members; however, after a scheduled renumbering by the club in August 2015, the number decreased to 156,916. In April 2017, Benfica reported they had a total of 184,264 members by 31 December 2016. Benfica has rivalries with Sporting CP and FC Porto, with whom it forms the "Big Three": Portugal's most decorated clubs. None of them have been relegated from the Portuguese league since its establishment in 1934. As Lisbon-based clubs, Benfica and Sporting have shared a rivalry for over a century; it all started in 1907 when eight prominent Benfica players defected to
1978–79 S.L. Benfica season handed the title to Porto, who gained a point with one match left. A week later, Benfica won, but so did Porto, who confirmed their back-to-back league title with 50 points, one more than Benfica. About the season, Mortimore said: "What a beautiful championship, with an appealing fight between Benfica and Porto. They (Porto) ended up being Champions because in the matches against us, they racked-up three points. But that was not the reason why he lost it. It was the poor results with Belenenses, Setúbal and Marítimo.". Two seasons without any honour was not seen since 1948, and two