Cristiane surpassed retired Germany star Birgit Prinz, who had 10 Olympic goals.
The 27-year-old Brazilian scored the record-breaking goal in the 80th minute after a perfect pass from Marta, picking up the ball inside the area and dribbling past the goalkeeper before hitting the open net.
"This is special, I knew I was tied and needed just one more to get the record for myself," said Cristiane, participating in her third Olympics.
She said the achievement meant even more considering she didn't even know if she was going to be playing at the London Games because of a right shoulder injury she sustained shortly before the tournament. She had already injured the same shoulder in late 2010.
"All I can think about is the time I spent trying to recover from my recent injury, practicing alone and not knowing if was going to be able to play in the Olympics," she said. "I was sidelined for four weeks and nearly got dropped from the squad."
Because of the injury, Cristiane started on the bench and entered the match at halftime to replace Thais Guedes.
"I had been training well but when you get to play it's different," she said.
Just before the goal Cristiane had another great opportunity to score but her close-range shot was saved by the Cameroon goalkeeper.
She also helped set up the penalty kick converted by Marta in the 73rd at the Millennium Stadium in Cardiff, Wales.
"She is one of our best players," Brazil coach Jorge Barcellos said. "We knew she could come through with a performance like that for us even from the bench."
Cristiane is trying to help Brazil win its first major title. The Brazilians had to settle for the silver medal in the last two Olympics after losses to the United States in the final. It also was second to Germany in the 2007 World Cup in China.
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