Great Britain's four won last weekend's World Cup opener

The four of Steve Williams, Peter Reed, Andy Hodge and Alex Partridge will combine with pair Colin Smith and Matthew Langridge and two others.

Both boats won gold last weekend in the opening World Cup event in Linz.

But BBC rowing reporter Martin Cross told Five Live: "It is not to make a super eight for the Bejing Olympics - it is being done to speed up the four."

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The next World Cup event begins in Amsterdam on 22 June, three months before the World Championships in Munich.

Head coach Jurgen Grobler has kept selection for the coxless four open throughout winter training, even though the current combination has yet to be beaten in 27 races.

Cross, an Olympic gold medallist in 1984, said: "Grobler has got a desire to improve them further, to stretch them. I think it's a brilliant strategy."

Marcus Bateman and James Orme, who raced in the second men's four in Linz, make up the eight, allowing the current first-choice eight to operate independently.