Great Britain's lightweight men's four took a narrow win over China to qualify for Sunday's final of the Belgrade World Cup.
Six other British crews also qualified for Sunday finals - the men's eight, women's double and quad and the lightweight men's double scull pair, women's single and double - in Serbia.
Eight British crews are also through to semi-finals and three face repecharge races as they continue their bids to qualify.
"It was a good day with more crews needing to work hard to progress tomorrow," said GB Rowing Team Performance Director David Tanner.
World champions Anna Watkins and Katherine Grainger won their double scull heat as did reigning Olympic lightweight men's double scull champions Mark Hunter and Zac Purchase.
"It's good to be back out there racing," said Hunter.
The men's four recovered from a slow start to win their heat and the men's eight repelled a late surge from Poland to take victory.
"It was good to start with a win in the heat after our first run-out as a crew," said 2011 world champion Alex Gregory of the four's performance.