Patience paying off for Britain
Luke Patience and Stuart Bithell will race against Australia for the gold medal
Great Britain's sailors Luke Patience and Stuart Bithell are mathematically assured of at least a silver medal in the men's 470 class at London 2012.
The pair have amassed a large enough points margin after Tuesday's first race to be sure that the third-placed crew - currently Argentina - cannot catch them.
Patience and Bithell now face a straight fight with Australia's world champions Mat Belcher and Malcolm Page for gold.
There is one more fleet race, before the medal race on Thursday.
Britain's Rachel Cawthorn booked her place in the final of the women's sprint kayak with an impressive performance at Eton Dorney.
The 23-year-old canoeist won her heat in the K1 500 metres impressively and then came second in her semi-final, raising the prospect of a medal for Team GB on Thursday.
Cawthorn was in fifth at the half-way stage of her semi-final but with the home support behind her managed to paddle up the field and qualify automatically, but there was disappointment for Louisa Sawers, 24, and 20-year-old Abigail Edmonds, who failed to reach the final of the women's double kayak.