Katherine Grainger began the Olympic Games as Britain's most successful oarswoman but will wake in the morning for the race set to define her career.
After three consecutive silver medals and 12 years as an Olympic bridesmaid, Grainger and her double sculls partner Anna Watkins are favourites to win gold.
Grainger has been here before. In Beijing the British quad were favourites only to be rowed agonisingly into silver by China in the final 250 metres.
While Grainger's first silver medal, won in Sydney, was satisfying, missing out in Beijing left her distraught and contemplating retirement.
But the whole of British rowing - the whole of British sport - will hope that this time is different. The portents suggest so.
Grainger, 36, and 29-year-old Watkins are double world champions and unbeaten in 22 races since they were first paired together in 2010.
The chemistry was immediate and they appeared invincible on Monday, smashing the Olympic record in a time four seconds faster than the other heat winners Australia. And Grainger insisted there is still more to come from the British crew.
"We were a bit surprised we got the Olympic record. Anna deliberately held us steady for the second half of the race," Grainger said. "Part of me would have loved to lift the roof off the boat and see how fast we can go but we know we've got that in the final. There's really quite a big amount to come."
Helen Glover and Heather Stanning powered to victory in the final of the women's pair on Wednesday, making them the first British female rowers to be crowned Olympic champions. Now Grainger and Watkins are determined to be the second triumphant women's team.
"This is the one we want more than anything," Grainger said. "Of all my Olympic experiences before, this is the important one."