There was heartbreak for British medal hopefuls John Gimson and Anna Burnet, who were disqualified for being over at the start of the mixed multihull sailing final on Thursday.
They appeared not to realise and did not go back to re-cross the line, with officials breaking the news mid-race.
The British pair, who are due to get married next month, had been well placed for silver or bronze going into the last race and were clearly distraught to hear their dream was over.
Gimson and Burnet welcomed their Italian training partners Ruggero Tita and Caterina Banti ashore, hugging them as the celebrations began on the beach for Italy, who notched up their second sailing gold of the Games after Marta Maggetti won the women's windsurfing.
Argentina's Mateo Majdalani and Eugenia Bosco held off Micah Wilkinson and Erica Dawson of New Zealand to secure silver, with the Kiwis settling for bronze in a trickylight-wind contest.
Banti and Tita said the joy at winning had been tempered by knowing their friends and rivals were out of the race.
"Even during our race we were feeling their pain," Tita said. "We know how much time they put into it and the time away from family and it's very hard," he added.