The USA brought the curtain down on the rowing regatta by winning their first men's eight title in 40 years.
The Netherlands took silver and Australia bronze, while double world champions Canada faded into fifth.
Earlier, Elisabetha Lipa won her fifth Olympic gold as Romania's women's eight won their third consecutive Olympic title ahead of favourites USA.
And Russia won the men's quadruple sculls ahead of the Czech Republic in second and Ukraine in third.
In other finals, Denmark won gold in the men's lightweight four with Australia second and Italy snatching third.
Ireland's Richard Archibald, Eugene Coakley, Nial O'Toole and Paul Griffin trailed home in last place.
Defending champions Tomasz Kucharski and Robert Sycz of Poland won the men's lightweight double sculls.
France's Frederic Dufour and Pascal Touron took the silver while Vasileios Polymeros and Nikolaos Skiathitis took a first ever rowing bronze for Greece.
And in the morning's first final, Romania's Constanta Burcica and Angela Alupei won gold in the women's lightweight double sculls.
Romania were defending champions and Burcica now has three Olympic golds while Alupei has two.
The Netherlands claimed silver while Germany took bronze, just ahead of Australia who had led for most of the way.