Erik Huseklepp pounced on an error by goalkeeper Eduardo to secure a famous win for Norway at the Ullevaal Stadion in Oslo and add to Portugal's early woes in Group H.
Portugal, the section favourites, drew 4-4 with Cyprus on Friday before this latest disappointment while Egil Olsen's side have got off to a dream start with maximum points from their first two outings following victory against Iceland. The only goal of this game came in the 21st minute when John Carew blocked a clearance from Eduardo and Huseklepp pounced on the loose ball before rolling it into the unguarded net.
Portugal had actually started brightest and worked an opening five minutes in, but Raul Meireles rushed his shot when put clean through by Tiago and fired over. Huseklepp's goal turned the momentum Norway's way and the home team enjoyed their best spell soon after, even if the Portuguese remained a threat with Manuel Fernandes and Ricardo Quaresma both going close in quick succession.
Portugal laid siege to the Norway goal at the start of the second half, but resolute defending restricted the visiting side to shots from distance. Hugo Almeida did put the ball in the Norway goal, but his effort was correctly ruled out for offside. With the clock ticking down Almeida was foiled by Jon Knudsen and Danny's shot cleared the crossbar narrowly as Norway held on. Olsen's men will hope to continue their winning start in Cyprus on 8 October when Portugal host Denmark.