Cuba's Dayron Robles stumbles on a hurdle as United States' Aries Merritt, fourth from left, leads the men's 110-meter hurdles final as Cuba's Dayron Robles is left behind during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Wednesday, Aug. 8, 2012.(AP Photo/Daniel Ochoa De Olza)
Cuba's Dayron Robles stumbles on a hurdle as United States' Aries Merritt, fourth from left, leads the men's 110-meter hurdles final as Cuba's Dayron Robles is left behind during the athletics in the Olympic Stadium at the 2012 Summer Olympics, London, Wednesday, Aug. 8, 2012.(AP Photo/Daniel Ochoa De Olza)