• 'I am not frustrated and I don't feel pressure,' says captain
• Expresses sympathy for plight of England and Wayne Rooney

Cristiano Ronaldo knows the rules of the game. It does not mean he has to like them. The Portugal superstar was discussing the travails of his old friend Wayne Rooney for England when his exasperation bubbled to the surface.

"Wayne tried very hard, he always does but he didn't play alone so it's difficult when things are not coming," he said. "When the team does not play well, it's always the big player's fault. But I am not worried."

The pressure on Ronaldo here is immense. The captain is expected to carry his team to glory and, when things do not go to plan, as against a defensive-minded Ivory Coast in Portugal's opening Group of Death match, it is him that the spotlight picks out. Ronaldo started brightly against the Ivorians and hit the post with a long-range drive but he faded badly as the game petered out into a 0-0 draw.

Into the bargain, the Real Madrid forward was kicked from pillar to post, according to the Portugal manager, Carlos Queiroz, yet he was one of only three players to be booked. Portugal appealed unsuccessfully against the yellow card, which was given after the Ivory Coast defender Guy Demel had fouled Ronaldo and the pair squared up.

"That was a clear refereeing error," Queiroz said. "It is not comprehensible that a player who is fouled as Cristiano was is shown the yellow card." Queiroz has urged referees to protect Ronaldo more assiduously. It was galling, he suggested, that Ronaldo must now tread carefully in the game against North Korea tomorrow; another caution and he would be suspended for Friday's showdown with Brazil.

Ronaldo does not need reminding that his last goal for Portugal was in a friendly against Finland in his penalty settled a friendly against Finland in February 2009. He has not scored in a competitive fixture since the Euro 2008 group-phase victory over the Czech Republic, two summers ago. Of course, he was reminded of these facts when he addressed the world's media ahead of the North Korea game. Cue more exasperation.

But Ronaldo has not got to where he has without a thick skin and it was his conviction that shone through. Portugal cannot consider anything but victory against North Korea. "It's all or nothing for us," Queiroz said. "There is only one result that we are interested in." Ronaldo intends to get it and the points, the forward insisted, were the only thing that mattered.

"It doesn't matter who scores the goals," he said, "or whether it's 1-0, 2-0 or 3-0. As long as we win and we can think about the last 16, that's the main concern. We are focused and confident that we can beat North Korea. To win the tournament is going to be very difficult but we have to believe it's possible. I am not frustrated and I don't feel pressure."

The shadow of Eusébio will hang over tomorrow's game. When the nations met in the 1966 World Cup quarter-final at Goodison Park, the Portuguese legend scored four times as his team came back from 3-0 down to win 5-3. It is sometimes forgotten that were it not for Eusebio's goals, England would have faced North Korea in the semi-final at Wembley.

The leading players at this World Cup have, by and large, not yet managed to illuminate it, although Ronaldo might have noted, when it was put to him, that Eusébio's free-scoring feats came in a less defensively robust era. The North Koreans, he predicted, would be certain to keep bodies behind the ball. Portugal will have to showcase patience and guile. "The most direct route through a barrier can sometimes be the most circuitous," said Queiroz, who will be without one of his creative midfielders, Deco, because of a hip injury. Deco intends to be back for Brazil.

Ronaldo accepted that Portugal had been "anxious" against the Ivory Coast because of opening day nerves, but said with that obstacle out of the way they could begin to relax. He himself might do well to rely on his instincts – he can sometimes appear to be trying too hard in an international shirt.

"It's normal that Cristiano looks better for his clubs," Queiroz said. "There, he works with the same players every day and he can develop a real understanding. But he has scored 20-plus goals for us so you can't argue he has underachieved. We're lucky to have him and I think that South Africa will be his hour."

Cape Town's Green Point Stadium has already seen France, Italy and England fail to beat supposedly weaker teams but Queiroz pointed out that the area held no fears for his countrymen. The Portuguese were the first Europeans to settle here. "The greatest achievement in our history occurred in this region so we are accustomed to confronting the Cape of Torments," he said.

Ronaldo hopes to prosper from the eye of the storm.Portugal (4-3-3): Eduardo; Ferreira, Alves, Carvalho, Coentrao; Simao, Mendes, Meireles; Ronaldo, Liedson, Danny.

North Korea (4-5-1): Myong-Guk; Jong-Hyok, Kwang-Chon, Song-Chol, Jun-Il; Yong-Jun, Nam-Chol, In-Guk, Young-Hak, Yong-Jo; Tae-Se.