 In 1999, Boldon ran 9.86 s twice in the 100 m before sustaining a serious hamstring injury which forced him to miss the World Championships in Seville - the only Championship he missed in his career due to injury.A silver medal in the 100 m and a bronze in the 200 m were Boldon's results of the 2000 Summer Olympics, which was a personal victory, considering his comeback from a career-threatening injury the year before.In 2001, Boldon tested positive at an early-season relay meet for the stimulant ephedrine, and was given a warning, but was not suspended or sanctioned, since ephedrine is a substance found in many over the counter remedies, and Boldon had been treating a cold.