Porto top the standings with 66 points after 29 matches, one ahead of Sporting who beat Academica 2-0 away.
Benfica, who defeated relegated Vitoria Setubal 1-0 away, are one point behind Sporting and battling for second place which provides an automatic spot in the Champions League.
Benfica president banned
Pacos Ferreira went ahead with a free kick by midfielder Antunes from an acute angle after 21 minutes. Brazilian striker Adriano grabbed the draw for Porto in a goalmouth scramble after 76 minutes.
Pedro Emanuel out for season
Yannick stays at Sporting