Iran: Beiranvand, Rezaeian, Hosseini, Pouraliganji, Hajsafi, Taremi, Jahanbakhsh, Ezatolahi, Ebrahimi, Amiri, Azmoun.
Subs: Mazaheri, Torabi, Mohammadi, Shojaei, Ansarifard, Khanzadeh, Ghoddos, Montazeri, Ghoochannejhad, Dejagah, Abedzadeh.
Portugal: Rui Patricio, Cedric, Pepe, Fonte, Guerreiro, Quaresma, William Carvalho, Adrien Silva, Joao Mario, Andre Silva, Ronaldo.
Subs: Beto, Bruno Alves, Fernandes, Joao Moutinho, Bernardo Silva, Dias, Ricardo Pereira, Bruno Fernandes, Goncalo Guedes, Gelson Martins, Mario Rui, Lopes.
Referee: Enrique Caceres (Paraguay).
Line-ups out:
Portugal vs Iran Line-up
Match Preview: So far, Portugal's all four goals in the tournament have come through Ronaldo and the Europeans will once again rely heavily on the talismanic striker if they want to make it to the second round.
Both the sides need a win on Monday to enter the Round of 16 and a loss for any of them could make life difficult.
With a win from two games, Portugal are placed second in the group with four points while Iran, who pipped Morocco 1-0 before falling against Spain, lie at the third place with three points.
Fernando Santos's side has till now appeared to be a one-man team with Ronaldo doing the most for his side on both occasions.
In 26 matches competitive matches since Santos took over in September 2014, Portugal have won 20 and lost twice, with one of those being a penalty shootout defeat by Chile in the 2017 Confederations Cup. Of those 20 wins, 10 have been by a single goal and most of the others were against weaker opponents.
In their last game against Morocco, Ronaldo was the only difference between the two teams. The Real Madrid star scored the only goal of the match in the fourth minute but Morocco did well to match the reigning European champions blow for blow throughout the encounter.
The north Africans were well organised in defence and midfield with the experienced Nordin Amrabat repeatedly troubling the Portugal defenders with his runs down the right wing.
The 'Atlas Lions' in fact dominated the second half as they went all out for the elusive equaliser. But a lack of quality in their final passes and some excellent defending by Portugal prevented them from scoring.
Even if they manage to enter the second round, the rest of the Portugal players must do better otherwise simply depending on Ronaldo will not carry them too far.
Before their last group game, Portugal defender Ruben Dias felt there is some anxiety in camp as they look to live up to expectations in the tournament as European champions.
"Anxiety exists because it's a World Cup and we are European champions and we want to get through the group and go as far as possible," Dias told mediapersons.
Dias, however, said that despite a slow start in this year's World Cup, his side could improve further as the tournament progresses.
"Sometimes, things aren't so good at the start and you start improving during the competition and gaining in confidence."
"This is naturalÂ…You start gaining confidence naturally," he added.
On the other side, Iran, Asia's number one team, benefited from a late own goal by Morocco to get their World Cup off to a winning start in Saint Petersburg before losing 0-1 to Spain in a hard-fought battle.
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.
The stability and pragmatism of Queiroz's seven-year reign, which will come to an end after the tournament with the Portuguese deciding to quit, has firmly established Iran as Asia's number one team.
Iran benefited from a late own goal by Morocco to get their World Cup off to a winning start in St. Petersburg but then lost 1-0 to Spain in a hard-fought match in Kazan.
On Monday, Iran will expect young striker Sardar Azmoun to fire and secure the Asian side a pre-quarter berth for the first time in their World Cup history.
Iran coach Carlos Queiroz has already declared the match against Portugal as the most interesting and important match.
"We go for it, with great belief and great determination to try to win the game," Queiroz said.
"When we arrived, no-one gave us a chance, but we still fight for our dreams," he added.
Iran have so far been impressive in defence and their defenders will have to once again come out with spirit to restrict Ronaldo from scoring.
Overall, a draw for Portugal will be enough to lift them to the next round while Iran need nothing less than a win to secure a pre-qualifier berth.
Iran vs Portugal: Watch out for
Cristiano Ronaldo has scored Portugal's all-four goals in the World Cup so far and the European Champions will be heavily dependent on the talismanic forward.
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.
Key stats:
Spain, who take on already ousted Morocco, and Portugal 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.
Iran’s Portuguese coach Carlos Queiroz was in charge of Spanish giants Real Madrid for the 2003-04 season. He also managed Portugal for more than two years from 2008, including the 2010 World Cup in South Africa.
Team Melli striker Sardar Azmoun has played his club football in Russia since 2013 and last year rejoined Rubin Kazan for a second spell.
Cristiano Ronaldo has scored all of Portugal’s goals in this tournament including a hat-trick in the 3-3 draw against Spain. His goal against Morocco made him Europe’s all-time leading scorer in international matches. Former Iran striker Ali Daei is the only one ahead in the world with 109 strikes.
The two sides have met twice, with Portugal winning both. The most recent fixture was in the 2006 World Cup finals in Germany where Deco and Ronaldo scored for Portugal.
Time: 11:30 PM (IST)
In today's Group B match, Iran vs Portugal match will take place in Saransk on Monday, June 25, 2018, at 11:30 PM (IST).
Iran vs Portugal match will be broadcast on Sony Ten 2, Sony Ten 2 HD, Sony ESPN, Sony ESPN HD in English Commentary and Sony Ten 3 and Sony 3 HD in Hindi Commentary.
Iran vs Portugal matches will be available for live streaming on Sony Liv also. And Both Airtel and Jio would broadcast the FIFA World Cup 2018 matches for free to their respective subscribers.