The competition format suffered changes for the second consecutive year, with the number of teams being reduced and the semi-finals being played on the same week of the final, in late January.
This result marked Benfica's first defeat in the competition since 31 October 2007 and put an end to a 42-game unbeaten run.
If two or more teams are tied on points on completion of the group matches, the following criteria are applied to determine the rankings: In all other rounds, teams tied at the end of regular time contest a penalty shootout to determine the winner.
Thirty-five teams competing in the two professional tiers of Portuguese football for the 2016–17 season are eligible to participate in this competition.
For Primeira Liga teams, the final league position in the previous season determined in which round they enter the competition.
In the third round, the 11 second-round winners and Vitória de Guimarães joined the four top-ranked teams from the 2015–16 Primeira Liga: Benfica (1st), Sporting CP (2nd), Porto (3rd) and Braga (4th).
[9] In the knockout phase, the four teams advancing from the third round contested one-legged semi-final matches for a place in the competition final.