Windsor: British rower Katherine Grainger captured Olympic gold in her fourth attempt on Friday, winning the women's double sculls with Anna Watkins at Dorney Lake.
The favored British crew won by more than a length and a half in 6 minutes, 55.82 seconds. Australia won silver and Poland took bronze.
Grainger sobbed after winning silver in the quadruple sculls at the 2008 Beijing Games, the third straight Olympics where she finished in the runner-up boat.
But since coming together with Watkins at the end of 2010, they haven't lost a race and beat the Olympic-best time by nearly five seconds in the heats.
It was Britain's second gold of the regatta. Helen Glover and Heather Stanning won the women's pair on Wednesday.
The 36-year-old Grainger is Britain's most famous female rower and an immensely popular member of the squad. She said she would "explode" if her boat crossed the finish line first and she nearly did just that, looking to the sky with her arms outstretched.
She then gave big thumbs-up to the adoring crowd in the packed grandstands.
When they climbed out of their scull, Grainger and Watkins, who was also in the quad sculls in Beijing, embraced.
They won by 2.73 seconds after going out hard from the start and eventually shrugging off the challenge of Australians Kim Crow and Brooke Pratley in the lane next to them.
Crow is also competing in the single sculls at the London Games. That final is on Saturday.
Magdalena Fularczyk and Julia Michalska, the 2010 world champions, finished more than nine seconds behind Australia in third.
Before the London Games, a British female had never won Olympic gold in rowing. With Kat Copeland and Sophie Hosking favorites to win the lightweight women's double sculls on Saturday, the host nation could end up with six female gold-medalists by the end of the regatta.