The British were supposed to dominate the Olympic road race in London, ushering sprint ace Mark Cavendish over the lumpy course in the Surrey countryside and delivering him to the finish at Buckingham Palace.
Instead, Kazakh rider Alexander Vinokourov boldly broke away for gold.
Four years later, things could be even more unpredictable when riders line up at famed Copacabana Beach on the first full day of the Rio Olympics. The first medal event of the cycling program will feature one of the most challenging road courses in Olympic history, a hilly ride on the Brazilian coast that could whittle the field to a handful of riders by the time they reach the finish at Flamengo Park.