Unlike in their first match against England, the Iranian players sang along to their national anthem before Friday's match against Wales as some fans in the stadium wept.
Some Iran fans confiscated Persian pre-revolutionary Iranian flags from supporters entering the Ahmad Bin Ali Stadium and shouted insults at those wearing shirts with the slogan of the country's protest movement: "Woman, Life, Freedom."
Small mobs of men angrily chanted "the Islamic Republic of Iran" at women giving interviews about the protests to foreign media outside the stadium.
Shouting matches erupted outside the security checkpoint at the stadium between fans shouting "women, life, freedom" and others yelling back "the Islamic Republic".
Many female fans were visibly shaken as Iranian government supporters surrounded them with national flags and filmed them on their phones.
One 35-year-old woman, Maryam, who, like other Iran fans, declined to give her last name for fear of government reprisals, started to cry as shouting men blowing horns surrounded her and filmed her face up close.
She had the words "Woman Life Freedom" painted on her face.
Another woman, Vanya, 21, who lives in Qatar, said she is terrified to ever go back to Iran after what she experienced outside the stadium on Friday.
"I'm genuinely afraid for my safety here," she said.
A group of fans wearing hats emblazoned with the name of the Iranian former soccer player Voria Ghafori, who was arrested in Iran on Thursday, said they had their hats stolen by government supporters.
"It's obvious that the match had become very politicised this week. You can see people from the same country who hate each other," said Mustafa, a 40-year-old Iran fan.
"I think the arrest of Voria has also affected society in Iran a lot."
Some fans said stadium security removed items with messages in support of the protest movement.
Ayeh Shams, from the US, who was at the game with her brother, said security guards confiscated her flag because it had the word "women" on it.
"We're first-generation American. Our parents were born in Iran. We're just here to enjoy the games and give a platform for the Iranian people who are fighting against the Islamic regime," Ms Shams said.
Some anti-government fans waved signs in support of the protest movement at Iran's first match against England earlier this week.
Before that game, Iran's players remained silent as their national anthem played.
On Friday, they sang along.
The unrest in Iran has been spurred by the September 16 death of 22-year-old Mahsa Amini in the custody of the country's morality police.
It first focused on the state-mandated hijab, or headscarf, for women, but has since morphed into one of the most serious threats to the Islamic Republic since the chaotic years following its founding.
Zeinlabda Arwa, a security guard at the stadium, confirmed authorities gave orders to confiscate anything but the flag of the Islamic Republic of Iran.
"Whether you're talking about Iran or Qatar or any country, you are only allowed to bring in the normal flag," she said.
An angry group of Iranian government supporters shouted at Elyas Doerr, a 16-year-old Iranian living in Arizona who was wearing the Persian flag as a cape, until he took it off and and put it in his bag. "They're not liking that it's a political statement," he said, adding other Iranian fans approached him to say they appreciated the gesture.
Before Friday's match, which Iran won 2-0, Iranians chanted anti-government slogans from rooftops in Tehran. Scattered protests also erupted in Kurdish towns in the country's west and across the central city of Isfahan on Thursday.
Iranian state TV on Friday devoted its main news bulletin to Iranians' soccer prowess, wishing the national team luck against Wales and airing a montage of Iranian goals throughout history.