If your typical Brazilian sports star is a brash, male footballer from Rio then Sarah Menezes is about as far from that cliché as it's possible to be.
The 22-year-old athlete comes from Piaui, a remote state in the north-east of Brazil.
It was judo, not football, that sparked her competitive instincts when she was nine years old, after watching a demonstration at school.
"I've always liked challenges, since I was a kid," she explains.
Sarah is third in the world ranking for her category (-48kg), which all but guarantees her spot at the 2012 Olympics in London. But her first big challenge in the sport was not on the mat.
She had to defy her parents' initial reproval when they heard that the youngest of their three daughters was taking up "a boy's sport".
"In the beginning my parents didn't accept it. I was very young and they said I had to study and be more ambitious, think of a career for my future. They'd say it was a masculine sport, but I insisted until I managed to change their mind," recalls Sarah.
Ironically, that little girl who would sneak out to practice after school without telling her parents now has the chance of being the first woman to win Brazil a gold medal.
In terms of results, judo is Brazil's second Olympic sport, with 15 medals - behind sailing, with 16. But women have only been able to win Olympic medals in judo since 1992. So far, Brazil has one female bronze, earned by Kathleen Quadros in Beijing.
Sarah has become a celebrity in her hometown. She comes from Teresina, the capital of Piaui, one of the country's poorest states. Her city is 2,500 km from Rio and Sao Paulo, where most of investments for sports tend to flow.
But Sarah is a girl with strong roots, and has stuck with her city. She travels often for competitions with the Brazilian Judo Team, but still lives with her parents and practices on a daily basis with the same coach, Expedito Falcao, who has been training her since her first year in the sport.
"Sarah is 'made in Piaui'. All that she knows, she learned in this place, training on this mat," says Falcao, pointing to the pitch behind him at the club where Sarah and other young athletes practice every evening from 8 to 10pm.
Falcao shares the pride for Sarah's successful career with most of Piaui, whose 3 million inhabitants for once have something to boast about to the rest of the country - and to the world.
"Sarah is a reference to the state. Although we are far away from the main Brazilian cities and have many difficulties, she broke this barrier and showed that we can go further and be stronger," he says.
Sarah has brought home 14 medals from the international judo competition circuit, including two bronzes from the last two World Championships, two World Junior Championship titles and three World Cup golds.
Her steps are closely observed by the local media in Teresina. While judo is usually dwarfed by huge pieces about football in Brazil's national newspapers, her medals make the headlines in Piaui.
Sarah also has a crowd of young admirers. For girls, the judoka who defied her parents and beats boys on the mat has become a role model. Because of her, more and more young girls are taking up the sport, her coach says.
Sarah's family lives in a simple neighbourhood, away from the centre of Teresina, where she and her two sisters grew up playing on the streets.
After a first year of frowns and some quarrelling, Sarah's parents, Rogerio and Dina Menezes, soon became great supporters. Her older sister Samia Menezes says they realised she was serious when she started bringing medals home.
"We started coming along to the competitions and she would always win really fast. We quickly realised that she had real talent," says Samia.
Her room is cluttered with medals, stuffed animals and a wall-sized picture of her at a podium receiving one of her gold medals.
A desk is kept tidy for her studies. In between her training and constant travels she finds time for university and is two years away from graduating in Physical Education.
Her aim is to help other children take up judo, especially girls. This year she will take the first step towards this goal, opening a judo training centre together with her coach in March.
"I want to give something in return for all the support I had and share everything I've learned from judo," Sarah says.
On the mat
It is high summer in Teresina when the BBC visit Sarah and their family at home. They show the same disarming hospitality we see everywhere in the city.
Like an informal ambassador to her state, Sarah insists everyone tries local specialties and typical fruits, as well as a regional drink made of cashew - the fruit widely known for the nut that grows on it.
However, her easygoing manner transforms when she fights in training. Facing her opponent, her relaxed smile gives way to a fierce, hypnotic gaze.
It is all part of her daily preparations for the London Olympics, her second Games. She considers herself more mature today than in Beijing, where she lost in the first round. She is now aiming for the gold.
Alongside her Japanese rivals in the world rankings, she believes she has another opponent to overcome.
"Myself - I'm my main obstacle to winning right now. I need to overcome my nerves more. Technically I'm already there - I've just got to win the fight inside my head," she said.