Eduardo's failed clearance allowed Erik Huseklepp to score into an empty net and earn the Norwegians a 1-0 home win on Tuesday, coming just days after another error led to Cyprus's late equaliser in the shock 4-4 home draw.
The keeper, who conceded just one goal at the World Cup, can be blamed for the errors, but his team-mates are no longer hiding the fact the whole side has been rattled by coach Carlos Queiroz's recent six-month ban for insulting anti-doping agents before the tournament in South Africa.
"On the pitch we try to concentrate, but sometimes this dark cloud affects us," midfielder Tiago said referring to the ban.
"The soap opera has to be resolved. It's not just the fans who want it settled, the whole of Portugal wants it," he added.
Queiroz has said he will appeal the ban, taking his case to the Court of Arbitration for Sport, but a meeting of the Portuguese Football Federation's (FPF) board on Thursday could lead to his sacking, according to media reports.
The FPF's role in the case has been heavily criticised. Queiroz's supporters say it has built up a case to try to fire the coach without paying him wages for the two years left in his contract, while his detractors say the federation has acted too slowly on firing him and damaged the team.
With just one point from their opening two games in Group H, the Portuguese have little margin of error left.
"It is a small group (with only five teams), just eight games and it is now a problematic situation... Norway have two wins and that is very important as they are theoretically the outsiders with Portugal and Denmark favourites," said interim coach Agostinho Oliveira.
The coach said he had been in contact with Queiroz, though not during the matches, but the pair have failed to minimise the impact of a long list of injuries headed by Cristiano Ronaldo as well as the international retirements of Deco and Simao.
Oliveira has been criticised for his team selections, particularly in midfield. Raul Meireles, Tiago and Manuel Fernandes started against Norway despite having barely played this season at their clubs, while the in-form Joao Moutinho was left on the bench.
Denmark, who beat Iceland 1-0 away, are likely to pose a stern test in Porto next month.
"Things are not going well on and off the pitch. We have to turn it around and start collecting points," captain Ricardo Carvalho said.
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