American Kerron Clement stormed to a surprise gold in the men's 400 metres hurdles at the world championships on Tuesday.
The 21-year-old ran a superb last 200 metres, clocking the year's quickest time of 47.61 seconds with Olympic champion Felix Sanchez taking silver for the Dominican Republic in 48.01.
Poland's Marek Plawgo claimed bronze in 48.12 with pre-race favourite James Carter fading badly over the final 150 metres to finish a disappointing fourth in 48.40.
Carter had finished second to fellow American Bershawn Jackson at the last world championships in Helsinki in 2005.
Jackson failed to qualify for the final in Osaka after clipping the last hurdle in Sunday's semi-finals.