Britain's Ben Saxton and Nikki Boniface claimed a silver medal in the Nacra 17 class at the World Cup Series in Genoa.
The duo went into the double points scoring finale in pole position.
However, their sixth-place finish saw Iker Martinez and Olga Maslivets of Spain, who were second in the race, claim the gold medal by just one point.
"We are gutted to have lost the lead after having it all week but we are really pleased with how we sailed in challenging conditions," said Boniface.
The 25-year-old from Polegate, East Sussex, added: "We came here with areas to work on and we've really progressed this week so we look forward to the European Championships in Weymouth next month."
James Peters and Fynn Sterritt were Britain's only other medal hopes of the day, beginning the 49er medal race in third overall.
A good start put them in gold medal-winning position early on but, as with Saxton and Boniface, they were hampered by Genoa's unpredictable light winds and came home ninth to finish fifth overall.