The teams, both wearing headscarves, long smocks and tracksuit trousers to avoid breaking Iran's strict dress code, finally run out onto a muddy pitch with torn goal nets six months late. But the players' passion and the enthusiasm of an empowered all-female crowd offer a positive message.

The film shows ecstatic Iranian women, who are not usually allowed into a football stadium – not even as spectators, jumping up and down on the stands, cheering and whistling, while a voice orders them through a tannoy to be more dignified.

The electric atmosphere among the women contrasts with frustration among men who, for once not allowed inside the stadium, have to peer in through cracks in the fence.

Director David Assmann said it was difficult filming in Tehran, particularly given the sensitive subject matter, although it helped that the documentary film and match were a joint project.

"I think without the film, the match would not have taken place," he said, arguing it put pressure on the Iranian authorities not to cancel the fixture altogether.

The obstacles faced by the German team included losing their sponsorship, failing to get the right paperwork and even having trouble finding long-sleeved tops and tracksuit bottoms for the players to wear at the match.

The film, which dwells mostly on the Berlin team's frustrating preparations and reservations about going, has a humorous side.

The German players, strapping young women who look almost comical in their bright white headscarves, frequently descend into infectious fits of giggles. But it is an Iranian player who steals the show.

Niloofar, who has dressed as a boy to train without a headscarf, has posters of British footballer David Beckham plastered over her bedroom and even dreams about him. "Luckily, he spoke Farsi in my dream," she giggles.

The young woman who rarely stops smiling is ultimately forbidden from playing the game, for reasons that are unclear.

The film, which ends with a 2-2 draw, will not be publicly shown in Iran.