Porto clinched their 26th Portuguese Premier League title after fierce rivals Benfica slipped to a 2-2 draw at Rio Ave on Sunday, extending their decade-long domination of Portuguese football.
The northern club won 2-0 at Maritimo on Saturday thanks to two penalties by Brazil winger Hulk.
Second-placed Benfica's draw left Porto with a six-point advantage and with only two matches remaining the "Dragons" have a better head-to-head record.
The title win means Porto, European champions in 1987 and 2004, have won eight league trophies in the last 10 seasons.
Thousands of Porto fans cheered and chanted in downtown Porto as the squad celebrated on a balcony in the Dragao stadium.
"This championship was very complicated but what counts is that we won it in the end," Hulk said.
"I was watching Benfica's match in a Brazilian restaurant and would prefer to have won the title on the pitch but this also counts."
The feat is a major achievement for Porto coach Vitor Pereira, who took over from Andre Villas-Boas in June last year, although it will be Porto's only trophy this season.
"It is not easy to substitute a coach that won so much as Andre did. This year was one of learning and I am sure that there are still many titles to be won and I feel it is my destiny to give this club many more titles," a smiling Pereira said moments after having been washed over with beer by celebrating fans.
"Today's joy comes from deep inside".
Pereira struggled at times to live up to his predecessor's glorious 2010-11 season but will take satisfaction from the domestic league trophy despite falling short of last year's treble of league, Cup and Europa League.