2011 World Championships in Athletics – Men's 400 metres

The men's 400 metres at the 2011 World Championships in Athletics was held at the Daegu Stadium on August 28, 29 and 30. Going into the Championships, defending champion LaShawn Merritt was serving a 2-year ban. The ban was still in effect during the USA Outdoor Track and Field Championships, so Merritt was unable to compete. Ordinarily, since 1997, the defending champion is automatically invited to the championships, but the United States stipulates that the champion must compete in the national championships. It took a special decision by USATF to allow Merritt to enter. Merritt had minimal racing opportunities prior to the championships.

2011 World Championships in Athletics – Men's 400 metres

The men's 400 metres at the 2011 World Championships in Athletics was held at the Daegu Stadium on August 28, 29 and 30. Going into the Championships, defending champion LaShawn Merritt was serving a 2-year ban. The ban was still in effect during the USA Outdoor Track and Field Championships, so Merritt was unable to compete. Ordinarily, since 1997, the defending champion is automatically invited to the championships, but the United States stipulates that the champion must compete in the national championships. It took a special decision by USATF to allow Merritt to enter. Merritt had minimal racing opportunities prior to the championships.