sentences:  Dix took further 200 m victories at the Eugene and London legs of the series, while Usain Bolt won the other three 200 m mid-season legs.He achieved a 100/200 sprint double at the 2011 USA Track and Field Championships, winning in the absence of Tyson Gay and Wallace Spearmon.Running in both the events at the 2011 World Championships in Athletics, he first secured the silver medal in the 100 m final – defending champion Bolt was disqualified for a false start and Dix was runner-up to another Jamaican, Yohan Blake, in a comparatively slow 10.08 seconds.