The players of the Iran national team did not sing the national anthem in the World Cup opener against England.
Iranian activists see it as a gesture of support for the nationwide protests in the country.
Before the game this Monday, they had hoped for a declaration of solidarity from the players.
The Iranian state broadcaster interrupted the live broadcast during the anthem.
The players could now face consequences.
There had been speculation in Iran that they might be banned if they remained silent at the anthem.
Iranian captain Ehsan Hajsafi on Sunday expressed his condolences to the grieving families of the victims in Iran.
The team has to accept that the conditions in the country are not good and the people are not happy.
The players are aware of that.
According to estimates by human rights activists, at least 360 people have been killed in the nationwide protests in Iran so far.
Iranian striker Mehdi Taremi said before the tournament that the team in Qatar did not want to be influenced by the protests at home.
"We also have other responsibilities towards Iranian society, but here our focus is on football," he said.