Paul Brotherton and Andy Hemmings started the day in the bronze medal position but then tactical errors pushed them back from ninth to 26th in the light airs race.
'We decided to retire because we were last and the only way God could help us was if the breeze died,' said Hemmings as he folded up the sails in the park in front of the British team containers.
'This means we have no chance whatsoever,' he said. 'It is definitely curtains. What it means is that we are now looking forward to the next championship.'
The gamble for Brotherton and Hemmings, who can discard their worst result, was that they would not improve yesterday on their 17th position in their fifth race. But in conditions like yesterday's the race is not over until the line is crossed and anything can happen.
In fact they only slipped two places to fifth in the overall standings and even then are only six points behind the bronze medal position they had so casually relinquished.
The example of Germany, who went from 18th to third on the final leg of the race, demonstrates the opportunity for improvement that the British pair squandered.
As the time limit of four hours approached it became increasingly obvious that the first boats would cross the finish line and they were led by Hungary's Gyula Nyari, who had made up 10 places on the last, slow leg to windward.
Once he had finished, the time limit was extended for everyone, including the gold medal leaders, Spain's Jordi Calafat and Francisco Sanchez, who had slipped from first to 10th.
The men were soon followed by the women with Spain's Teresa Zabell making almost certain of yet another Spanish gold medal as she won again.
The cliffhanger struggle by Britain's sailors to grab some of the medal glory continued yesterday.
Stuart Childerley improved his chances in the Finn class as Jose Maria van der Ploeg clinched the defence of Jose-Luis Doreste's 1988 gold with a race to spare. America's Brian Ledbetter defends his silver medal slot today and Childerley, with the slimmest of holds on the bronze, knows that four others are in tight formation behind him.
David Howlett and Phil Lawrence were never expected to emulate Mike McIntyre and Bryn Vaile's hijack of the Star gold medal in 1988 and finished 14th.Reuse content