Carlos Queiroz has built the Persian Stars into a formidable and physical defensive unit, but Stephen Keshi's men need a win if they are to kick on from their 2013 AFCON triumph.
This is Nigeria's fifth World Cup while and the fourth for Iran, which qualified for the tournament thanks to its mean defense, which conceded just five goals in 10 Asian qualifying matches.
"Iran's qualification was like a crossing through hell", said coach Carlos Queiroz after his team achieved its objective, and for the Portuguese now it is time for the crossing through heaven.
But Nigeria is not a team prone to gifting matches to the opposition, and Stephen Keshi wants his team to demonstrate the form that made it current champion of Africa.
The Super Eagles arrive in South America hoping to improve on their best return from a World Cup; they reached the round of 16 in 1994 and 1998.
Iran does not habitually create many chances but their strength - aside from that back line - lies in its aerial threat, and it is this which laid the foundation for its qualification.
Queiroz's men go into Group F as heavy underdogs but if they are able to keep things tight at the back and get the ball into the penalty area from the flanks, they are capable of confounding the doubters.
Nigeria, for its part, is not the team which finished bottom of its World Cup group in South Africa four years ago. Keshi has built a strong, dangerous team which was deservedly crowned king of its continent in 2013.
Keshi varies his system depending on the opponent, but usually sets his team up in a 4-3-3 formation or a 4-2-3-1 which can become as attacking as a 4-2-4 when the situation allows it.