Seven-minute salvo transforms Portugal
Instead of approaching their final game against Brazil nervously keeping an eye on Ivory Coast's progress against the Koreans they can face the five-times champions with qualification virtually secure and in the mood to top the group.
It was not looking so good at halftime on Monday when they had just a 1-0 lead through a Raul Meireles goal against the surprisingly positive Koreans.
However, a devastating spell between the 53rd and 60th minutes changed everything, starting when Meireles exchanged passes with Hugo Almeida to set up Simao Sabrosa for the second goal.
As the passes began zipping over the sodden Green Point pitch, Almeida headed the third and Tiago made it four.
With the pressure lifted, half an hour of free-flowing football followed, with three more goals in the last 10 minutes as Ronaldo broke his 16-month drought and Liedson and Tiago put the gloss on.
The players who had looked so edgy against Ivory Coast came off the pitch with belief coursing through their veins.
"We needed to win but the way we did it was unbelievable. It was a great performance and we just have to keep it going," said midfielder Pedro Mendes.
"Of course we knew we were capable of that, we have the players for that. It was difficult for a while but we did well and now everybody is confident."
Coach Carlos Queiroz also deserves huge credit. He set the scene for the match, telling his players to work hard to first secure the win and then, once it was safe, to go forward in search of goals.
He also made four changes to the starting lineup which all paid off handsomely.
Injured Deco was replaced by Tiago, who delivered a superb pass for the opening goal then scored two himself.
Simao came in for Danny in midfield and also capped a great display with a goal, as did forward Almeida, preferred to Liedson. Fullback Miguel was the other change for Paulo Ferreira.
Now Portugal face Brazil where a point will guarantee progress and even a respectable defeat would probably see them through.
Brimming with confidence, however, Portugal's players want more. "Now we can breathe, we can think about winning the group," said Tiago.
"First is better than second and why not? We score goals, play good football and go into the game with confidence."