The Jamaican sprinter Asafa Powell has pulled out of the 100 metres at the world championships starting this weekend in Daegu, South Korea, spoiling a highlight anticipated showdown with his countryman Usain Bolt.
Bolt will be the only survivor from the podium at the 2009 championship following Powell's withdrawal because of a groin strain, though the former world record holder is hoping ro run the 4 by 100 metres relay.
The world's second fastest man Tyson Gay didn't make the US team because of injuries.
