Medina Spirit, whose victory in the Kentucky Derby has been cast in doubt after a positive drug test, has arrived at the Pimlico race track ahead of Saturday’s Preakness Stakes, the second leg of horse racing’s Triple Crown.Medina Spirit, whose victory in the Kentucky Derby has been cast in doubt after a positive drug test, has arrived at the Pimlico race track ahead of Saturday’s Preakness Stakes, the second leg of horse racing’s Triple Crown.