The women's quadruple sculls team are out to defend their title in Eton

Grainger and her team-mates Debbie Flood, Sarah Winckless and Frances Houghton needed a sprint finish to defeat Russia by just 1.07 seconds.

Grainger is chasing a hat-trick of world titles.

The women's eight, featuring Olympic medallist Elise Laverick, finished a disappointing last in their heat.

The women's quadruple sculls success was one of four victories for the British team.

Richard Chambers and Chris Bartley won the morning's opening heat in the men's lightweight pairs.

The women's lightweight quadruple sculls of Laura Ralston, Lindsey Dick, Sophie Hosking and Hester Goodsell beat reigning champions Canada in their heat.

The lightweight men's pair of Mark Hunter and James Lindsay-Fynn comfortably won their race and the men's eight also moved into the semi-finals despite being edged into second by Germany by 0.01 seconds.