Women in Iran have been prevented from attending the Kish Island Open leg of the Beach Volleyball World Tour, despite assurances from organisers they would be allowed in the stadium.
Several women posted on Facebook that they had been turned away from the stadium at the gates, as per Iran's law banning women from stadiums, being told by guards "it's forbidden".
The women had to resort to watching the match from the roof of a nearby coffee shop, which let them in free of charge and allowed them to watch the game.
Women have been banned from football stadiums since 1979, and banned from attending volleyball matches since 2012, with no reason ever given for the ban – a low blow in a country where volleyball is very popular and stadiums were previously celebrated for their family atmosphere.
The International Volleyball Federation (FIVB), which agreed the match would be hosted on Kish Island in Iran only as long as women were allowed to attend, said there had been a security misunderstanding that had prevented women from being allowed in the stadium, but added that the problem was now resolved.
FIVB spokesman Richard Baker told Associated Press: "There were some misunderstandings with regard to security" at the 16 February match.
"There have been misunderstandings throughout the day, and we have had to seek clarification," Baker said, adding the Iranian federation "has the best intentions but there are cultural issues".
But Human Rights Watch said the organisation had failed women and questioned why FIVB had chosen to hold the match in a country not renowned for its fair treatment of women.
"Brave Iranian women who took the FIVB at its word were turned away at the turnstiles this week. That is a black eye for the sport of volleyball, and a setback for women's rights in Iran," said Minky Worden, director of global initiatives in a statement.
"This sorry episode highlights the shortcomings of the FIVB's strategy with the Iranian government, and contradicts their claims that all Iranian fans are welcome."
She added: "This episode is far more serious than a 'slight misunderstanding,' since it spotlights the broader risk the 2012 ban imposes on Iranian women who seek to attend volleyball matches.
"It is not fair to ask women to come to the matches without protection and planning for the likelihood that women would have trouble at the gates as in past years."
Human Rights Watch also urged the FIVB to pressure Iran to lift its restriction on women entering stadiums.