BEIJING (AP) — This world title came in a tactical race for David Rudisha, so very unlike the wire-to-wire run at the London Olympics that earned him a gold medal and a world record in the 800 meters.For the 26-year-old Kenyan, it felt just as good.Rudisha missed the chance to defend his world title two years ago in Moscow because of an injured right knee which restricted him to just two races that season.