She did well in the tournament, twice using the Four Knights defense, but to the President of the Iranian Chess Federation, Dorsa practically committed an act of treason.

Iran’s Chess Federation President, Mehrdad Pahlevanzadeh, wasn’t unhappy with Dorsa’s play, but instead, with her headwear. In her long hair, she wore a headband, not a hijab, Iran’s traditional headscarf.

The hijab became a compulsory accessory for women after the 1979 revolution. Many Iranian women are protesting against the Hijab law, saying that it has makes harassment worse in Iran.

Dorsa’s rebellious act resulted in Pahlevanzadeh’s announcement on Monday that she would be banned from the national team.

Her 15 year old brother, Borna Derakhshani, faced off against Israel’s Alexander Huzman in the tournament, and was also banned from the team. His offense was agreeing to play an Israeli opponent. 

“Unfortunately, what shouldn’t have happened has happened. Our national interests have priority over everything,” Pahlevanzadeh said.