Quaresma made way for Bernardo Silva as the game entered its final 20 minutes, while Iran brought on Saman Ghoddos for Jahanbakhsh, Ghoddos swiftly into the action as he span on the edge of the area but lashed wide. "We believe in what we're doing and we've had a pretty good start to this competition, but there is room for improvement", added centre-back Jose Fonte.
On Monday, Portugal's players will meet a familiar face in the opposition technical area in Iran coach and compatriot Carlos Queiroz, who coached the side from 2008 to the South Africa World Cup in 2010. Even if Iran contains Ronaldo, Portugal has enough weapons to get a goal - and that could be enough. "We knew this, we didn't come here to play easy teams", he said.
Beating Portugal would send Iran into the best-of-16 round in the World Cup, the biggest win in the country's history.
"Messi is very good, but it is clear that he is very good because he is surrounded by extraordinary players (at Barcelona)", Simeone said, in an audio recording published by Spanish media outlets.
"We have a lot of respect for our rivals and it's a very important game because it's going to give us the chance to get through the group phase".
As ever, Ronaldo will be the man to watch for Portugal against Iran. Iran will advance to the round of 16 if they win.
Portugal and Spain have tied on points and goal difference after winning two games. Following a draw against Spain and a win against Morocco, Portugal only need a draw in order to book a ticket to the next round with Morocco already knocked out.
Carlos Queiroz's Iran are now sitting at the third spot of the four-team group standings with three points, one behind group leaders Portugal and second-placed Spain.
Portugal is favored to beat Iran, and all it needs is a draw to secure its advancement.
Both sides have faced each other only once. Team Melli showed plenty of spirit despite losing 1-0 to Spain.
45' GOAL! Iran 0-1 Portugal: What a brilliant goal from Queresma!