Already assured of a place in the last 16, Brazil were on Friday without suspended playmaker Kaka, rested Robinho who had complained of muscle fatigue and were also missing the injured Elano, who scored in each of their first two games.
Even so, they dominated an often petulant, bad-tempered match against their former colonial masters, who themselves needed a point to absolutely guarantee they would qualify from Group G and showed little appetite for adventure.
Robinho, who forgets the problems that have dogged his club career when he puts on a Brazil shirt, has been one of their liveliest players here but Nilmar proved an able replacement.
The Villarreal striker, who has the impressive tally of eight goals in 15 internationals, was twice close to opening the scoring in the first half and his close control and speed made him a constant nuisance for the Portuguese rearguard.
The absence of Kaka was more keenly felt, especially after he set up two goals in the 3-1 win over Ivory Coast last Sunday when he appeared close to returning to his best.
Kaka's explosive bursts from deep in the midfield, vision and clinical finishing, often from long distance, make him one of Brazil's most feared players, even when he is not fully fit.
DUNGA FRUSTRATED
After Brazil's sixth goalless draw of his nearly four years in charge, coach Dunga again expressed frustration at the way opponents shut up their defence when they play his side.
"All teams take extra care when they face Brazil, there was nothing unusual about Portugal's tactics," he said.
It was a rather odd complaint from Dunga, who is himself much more comfortable when Brazil - who had scored in every World Cup group match since their 0-0 draw with Spain in 1978 - can play on the counter-attack.
Under Dunga, Brazil's best results have come away from home, where their opponents are forced to come out and attack.
Their World Cup qualifying campaign included 4-0 wins in Venezuela and Uruguay, a 3-0 win in Chile and a 3-1 win in Argentina while home results included goalless draws against Venezuela, Argentina, Bolivia and Colombia.
For all their lack of imagination, Brazil at least proved they are difficult to break down and only once looked in danger but were let off when Raul Meireles fluffed a chance. They have won 18 of their last 21 games and are unbeaten in nine.
Portugal never looked like a team who won their last game 7-0 and their performance had fear written all over it. But they are in the last 16 for the second World Cup in a row even if a chorus of jeers drowned out the vuvuzelas at the end.
