Spain want to fully concentrate on their upcoming game against Iran despite recent turbulences following the change of head coach, coach and players here said on Tuesday.

"The Iranian team are very strong, both in defending and attacking. They have very clear ideas about what they want to do. And they are very strong physically," Spain's new coach Fernando Hierro told a press conference at the Kazan Arena here.

Hierro replaced Julen Lopetegui as Spain coach 26 hours before their opening World Cup game against Portugal. The 2010 world champions drew 3-3 with the Portuguese side led by star player Cristiano Ronaldo after a fierce battle.

"Now we have to forget Portugal and concentrate on Iran. It's our second game, and it will be hard. We need the three points," said Hierro, adding that a win would give them an advantage in Group B.

"We want to do everything in our power. We know it will be a hard game, and our opponents are very strong. But on other hand, we have done many things right, and we have to trust ourselves," he added.

Andres Iniesta, Spain's star midfielder, echoed Hierro's words, saying that the team are more than ready to go forward.

"We want to forget that change (of coach). It has been a difficult situation for anyone. Now we want to concentrate on what we have to do, on what we have," he said.

The Barcelona midfielder pointed out that one of the strengths of the team lies in that most of them know each other very well after playing together for many years. "We have always been a very united team. In the end, I know we all trust each other blindly, and we try to defend the same idea and concept," he said.

The 34-year-old veteran player is probably playing his last World Cup. When asked about what achievement he wants to make, he said that athletes always want to achieve the highest possible title, and they are now hoping to win the World Cup here.

"But on the other hand, we know it's not going to be easy, and we will have to work very hard. Though we have big dreams, we want to concentrate on what we have to do for the next step," he said.