Rio Olympics 2016: Great Britain win gold in men's four
Great Britain's rowers claimed a fifth consecutive Olympic title in the men's four in Rio.
Mohamed Sbihi, George Nash, Constantine Louloudis and London 2012 winner Alex Gregory finished in five minutes 58.61 seconds.
Australia pushed their rivals hard but eventually came in 1.83 seconds behind to take silver, as Italy won bronze.
Britain's gold came shortly after compatriots Helen Glover and Heather Stanning won the women's pair.
Their medals added to the silver won by Katherine Grainger and Victoria Thornley in the double sculls on Thursday.
However, London 2012 bronze medallist Alan Campbell failed to progress to the final of the men's single sculls after finishing fourth in the semis.
Past Olympic champions in Britain's men's four include Sir Steve Redgrave, Matthew Pinsent and James Cracknell, and the boat traditionally contains GB's best rowers.
This year's crew came into the Games as favourites, having secured World Cup wins at regattas in Poznan and Lucerne, and they were victors by a comfortable margin to add to titles won in Sydney, Athens, Beijing and London.
Australia, who have now finished runners-up at the last three Games, were only 0.22 seconds behind at the halfway stage but faded in the last 500 metres of the 2,000m course.
"I didn't know what was happening four years ago but today sitting on the start line was horrible, it was tortuous," said Gregory.
"But we nailed that. It was our perfect race at the right time on the right day."
'They're better than us'
When asked how the 2016 men's fours win compared to Britain's four previous victories in the event, BBC pundit Redgrave, who won his fifth rowing gold at the 2000 Olympics, said: "You have to be better than the year before and the five years before. If you stay the same you will not stay in the same position.
"If we were side by side, our best against their best, we would be struggling to get into a final that is how much it moves on.
"They're better athletes. They row better, train better and make their boat go faster."
Cracknell - a winner in Sydney and Athens - said on Twitter: "Fantastic, gold for the men's four. Never in doubt, five Olympic golds in a row in the men's four and this was the best."
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