But there was no such comfort for the British pair of Andy Triggs Hodge and Peter Reed as they struggled after a poor start and were blown away by the New Zealand pairing who have been unbeaten since they came together in 2009, Hamish Bond and Eric Murray.

The British pair, both members of the four which took gold at the Beijing Games, worked hard to get back in touch with the race leaders, passing the Canadian pair 200 metres from the end, but they had left it far too late to make an impression upon the crew whom they have yet to beat, who finished six seconds ahead of them.

"We have to keep trying to get ahead of the Kiwis," said a disappointed Reed afterwards.

"They are only human as well and they feel pain so we hope we can overtake them."

For Grainger and Watkins, it was as if they had never been away as they defeated the Australians who finished one place behind them at last year's World Championships, Kerry Hore and Kim Crow, although the British pair needed to find a late burst of speed to withstand their competitors.

"We knew we would be put to the test," said Grainger.

"The Australian boat was incredibly strong."

Britain's women's pair of Helen Glover and Heather Stanning defeated the New Zealand pair which had beaten them to world gold last year, Juliette Haigh and Rebecca Scown.

New Zealand's 24-year-old Emma Twigg won her first World Cup gold in the single scull, while the Czech Republic's world champion Ondrej Synek beat New Zealand's former world champion Mahe Drysdale to win the men's single sculls.

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