A woman falls to the ground after receiving a blow to the head. Her attacker continues to circle above her, threatening more to come when she gets to her feet.
It is all taking place within Kabul's main stadium, the same place where the Taliban used to publicly flog and even execute women.
Thankfully the Taliban, who banned women from taking part in all sports, are long gone. Goodness knows what they would have to say about the scene in front of me.
About 20 young women, wearing headscarves and bright orange boxing gloves, are trading the most unladylike of blows.
"The first punch that I got was on my nose and it hurt very much and it also bled and was very painful," says Sonaya, a teenager with long dark hair.
"But after a while the pain went away and I realised I could learn from that punch. It was the only punch in the face that I've had so far in here."
She takes her boxing seriously. Like others here she hopes to qualify for a future Olympics and has been training hard.
I asked this rather shy looking girl with a sensitive smile whether she ever returned the favour.
"Yes, I have punched lots of girls on the nose," she says. Have you knocked anyone out? "No, not yet." Are you working on it? "Yes."
In a country where many husbands do not even allow their wives to leave their homes, never mind step into a boxing ring, what do Sonaya's family make of her chosen sport?
At first, she says, her father was very unhappy and frequently asked her to stop. But now he has accepted the idea on the grounds that the exercise is good for her health.
Mike Thomson reports from Afghanistan for the Today programme. Listen to his reports weekdays at 0600 GMT on BBC Radio 4
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Another member of her family took much less convincing.
"My mother has been encouraging me a lot. She tells me to practise hard and then go and enter a foreign competition and come back as a champion," she says.
Trainer Nasar, a middle-aged man with a bright red shirt and Bobby Charlton-style comb-over, admits that many families are not happy about their daughters donning gloves.
"We have lots of problems with parents here in Afghanistan," he says.
"We cannot force them to let their daughters train here. But I think those families that allow their girls to exercise should also let them choose what sport they want to do instead of stopping them doing boxing."
Happily for Terin, who sports a bright blue anorak and multicoloured head scarf, her parents had no objections. Though given this young women's attitude to those who cross her, that is perhaps just as well.
"I don't like fighting but when it's necessary I want to be able to defend myself," she says.
"There are a lot of street boys who harass girls and women. They think girls are weak. Now we have the chance to prove them wrong. I can defend myself and punch boys who are disrespectful to me."
Have you ever punched a boy, I ask.
"Yes, recently I was in a book shop and there was a guy who came in after me and he put his hand in my backpack.
"At first I didn't do anything but when he did it a second time, I punched him. His nose and mouth was covered in blood.
"When I left I could hear his friends making fun of him. They were saying 'Shame on you, you were hit by a girl.' I don't think he'll ever bother another woman. Now he knows how to treat them. "
The combative Terin has ambitions to go to medical school and become a doctor. But, it seems, she has no intention of using her medical skills to patch up boys she has punched.
"When I punch someone I will never go back to treat him, because he has to learn from his mistake," she says.
One could be forgiven for wondering whether, after several decades of war, perhaps the last thing Afghanistan needs is for its women to start fighting each other.
But Sonaya, who is hoping that she and her fellow female boxers will qualify for next year's Olympics in London, believes their success in the ring might spark harmony rather than hatred.
"The difference between the long-term fighting in Afghanistan and boxing is that the war is destroying things and ruining the reputation of the country. But the fighting that we are doing in a ring in front of each other is friendly fighting and a sort of message for peace."
Taking part in sport is new to women in Afghanistan, and some are taking advantage of this freedom by donning their boxing gloves and striking a blow for equality.