Britain's Tom Aggar claimed victory in the para-rowing arms and shoulders single sculls at the World Cup regatta at Eton Dorney.
The 2008 Beijing gold medallist, 29, lost his unbeaten international record when he finished fourth at last year's London Paralympics at the same venue.
But he beat 2012 bronze medallist Aleksey Chuvashev by over six seconds, with fellow Briton Andy Houghton third.
Meanwhile, Britain's mixed coxed four beat Ukraine in a head-to-head race.
London gold medallists Pamela Relph and Naomi Riches joined newcomers James Fox and Oliver Hester - plus cox Oli James - to claim another title.
Aggar admitted he was "devastated" by his failure to win a second Paralympic medal last year, but was in strong form this time, winning his heat comfortably before following up in the final, with Russian Chuvashev well adrift and Houghton next home in third.
"It was tough racing conditions all the way down but I showed good strength and put together a good race and I'm really pleased with the result," he told British Rowing afterwards.
"About halfway through I noticed I was edging through and after that I felt confident and strong.
"Last year I underperformed and it is special to win here after the disappointment of last year and it makes up for it a little."