Cristiano Ronaldo has scored 's all-four goals in the World Cup so far and the European Champions will be heavily dependent on the talismanic forward to see them through against a stoic in their final Group B match on Monday.
Ronaldo's hat-trick in the 3-3 draw against Spain gave Portugal a vital point while an early headed strike, which made him Europe's all-time top international goal scorer, against Morocco proved enough to bring home three points.
Portugal and Spain, who take on already ousted Morocco, are on four points and need a draw from their respective matches. But Iran are a point behind with three and must beat Portugal to progress.
The European sides will not only aim for victory but will also try to outscore each other with the top spot in the group set to be decided on goal difference.