Vicente del Bosque has described Spain's Euro 2012 semi-final with Portugal as the most important game of their lives. The Spain coach was also joined by Andrés Iniesta in defending his team's style amid accusations that they have become boring, and the midfielder hinted at the tiredness creeping into Spain's game when he called on his team-mates to make "one last push" to reach the final on Sunday.

"Both teams have an enormous responsibility," Del Bosque said. "We have the responsibility to defend the title; Portugal have the responsibility of knowing that they are at the gate of the best success in their history. We both have great pressure but I couldn't quantify who has more. I would say it's about 50%. This is the most important game of our lives."

Del Bosque continued: "We hope that we will keep progressing and stay in the elite of football. We have spent the whole of our lives looking for a style and now we have one that has been successful. Yet there are always people who are not satisfied. Our philosophy has got us here.

"I would prefer [Portugal] to play deep. I like us to be in the opposition's half and to have possession of the ball. I think that we have the players and the resources to open up defences."

Del Bosque was also asked if England could emulate Spain's playing style and whether that might be the way forward. He said: "I would call England the fathers of European football but the game has tendencies. At the last World Cup, Germany, Holland and Spain opted for a style that was more combinative and they stood out above the rest. Football has been globalised now and it goes through certain tendencies; that one is predominant now. I think England do have players of that style. They could do that perfectly well because they have very good players."

"Football is great because not everyone likes the same thing," Iniesta said. "Variety is nice; it's good to have a diversity of opinions. We have a way of playing that has brought us success and for us there is no other way. Those opinions [attacking Spain] are perfectly respectable but it is true that when there is [only] one team that always wants to attack and has a rival that only wants to close off, drop deep, and avoid danger, of course the football is not as attractive as when both teams want to win and open up to attack each other.

"Let's not forget that we changed Spanish football two years ago. And let's not forget how we did it."

There have been complaints about Spain travelling back and forth between Ukraine and Poland for the last two games with players admitting to suffering fatigue during the quarter-final. Del Bosque said that was not something that Spain should worry about too much. Asked about the fact that Spain have two days fewer to prepare the semi-final, Iniesta said: "At this stage we just want to play and not even think about those two days. That's the way the competition is set up and on other occasions it has maybe favoured us – like against France [when Spain had an extra day of preparation].

"We have to focus on playing well, being precise, effective. When the competition ends we can evaluate the level of tiredness but that's secondary now. There are only two games to go. We have to make a last effort of the tournament and we're focused on that."

The Portugal manager, Paulo Bento, insisted that Portugal would not simply wait for Spain but would look to attack them. "There will be moments when we can combine," he said. "We are aware of the fact that we are up against a team that has been better than the rest, the best team in the world. We will need to be patient and await our chances. If we have chances on the break we have to take them. But we will pressure them and we think we can cause them problems. We are not going to just defend all the time. We have reached the semi-final playing very well."

Bento added: "There are parts of Spain's game that are not as strong, where they are vulnerable. They had difficulties against Italy and against Croatia. And against France they did not create too many chances. But we will not be using those games as a model; we will be using our games as a model, focusing on what we have done well. Spain are defined above all by ball possession but we will be faithful to our own qualities.

"There is nothing lovelier than a semi-final, the chance to reach only the second final in our history. We have worked for this moment. There is no anxiety but we know that we have a great responsibility for the Portuguese people."