The end result additionally ensures that final yr's champions Sporting will end 2d, and qualify for the Champions League organization degree, with Benfica 0.33.
Nigerian left-lower back Zaidu struck on a counter-attack minutes into stoppage time to put Porto nine points ahead with one round of games to play.
Sporting journey to Portimonense later Saturday and have an 8-factor side and a game in hand on Lisbon opponents Benfica.
Benfica, who reached the area-finals of the Champions League this season, will go into the qualifying round of the opposition.
Before their first league defeat this season, at Braga two weeks ago, Porto, beneath instruct Sergio Conceicao, set a brand new Portuguese league unbeaten document of 58 games.
Porto could be able to crown their season with a double, when they face Tondela, sixteenth in the league, within the Portuguese Cup final on May 22th.
