Also in 2001, at the World Championships in Edmonton, Alberta, Canada, Boldon finished fourth and out of the medals in the 100 m with 9.98 s, and then ran the second leg of his country's 4 x 100-metre relay, finishing third in the finals. This was Trinidad and Tobago's first 4 x 100 m relay medal in either World or Olympic competition and Boldon states that making national history with this team of young men (the average age of his teammates was 19) was his greatest accomplishment in his career. The colours of his 2001 World Championship medals would change in 2005 as both his placings were improved – he received bronze in the 100 m and the bronze relay medals were upgraded to silver after all the times and performances of the American sprinter Tim Montgomery (who was second in the 100 m and won the 4 x 100 m with the US team) were nullified due to serious doping violations. That brought Boldon's career total to four World Championship medals, to match his four Olympic medals.