Spain coach Fernando Hierro says they must not be complacent facing World Cup opponents Morocco.

He believes this final group match is a potential banana skin and is urging his players to give their all.

"Experience tells us that these kinds of matches are trap games, ones which are very difficult because you come up against a team with nothing to play for and where all the players want to vindicate themselves," Hierro told Radio MARCA.

"If we want to have a good match and win then it'll have to be because of what we do."

Looking back on the 1-0 victory over Iran, Hierro was happy with the performance and pointed out how good Iran are at defending.

"It's really difficult to play against a team that lets in very few goals," he said.

"Of course we evaluate our performance and analyse everything in order to improve.

"This World Cup is teaching us that nobody will win matches easily."