The British women's lightweight double enjoyed a successful start to their campaign, dominating their heat and cruising to a clear-water victory over New Zealand.
Edinburgh's Sophie Hosking and Katherine Copeland, world championship bronze medallists last year, made a lightning start and pulled clear in the second 1000 metres in a supreme exhibition of sculling.
New Zealand set the world's fastest time in Lucerne earlier this year and won gold at the Munich World Cup regatta, but they could not live with the British crew.
Hosking and Copeland were seven seconds faster than world champions Greece, who won the second heat and 19 seconds up on third heat-winners China.
"The feeling when you cross the line and the noise going up — if I could bottle that emotion and sell it, I'd be a millionaire. That is what sport is about," Hosking said.
"We felt like we were within ourselves and there is still more to come. We can row better together, that was a heat row and we need to step it on."
Britain's women's eight finished third in a heat dominated by the United States, who are the reigning world and Olympic champions and unbeaten since 2006.
Britain finished third after Australia withstood a late push but they should progress to the final from Tuesday's repechage.
"It was frustrating today. It wasn't our best row. Probably good to get one like that out of the way," said Jess Eddie.
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