Usain Bolt has admitted that it is "sad" that doping allegations are threatening to overshadow the upcoming World Athletics Championships in Beijing.

Bolt will go up against Justin Gatlin, who has twice been banned for doping offences, in the 100m, but the Jamaican sprinter has insisted that the focus shouldn't be entirely on his event, with the sport as a whole having a "responsibility" to try to ensure that it is seen in a better light.

The 28-year-old is quoted by BBC Sport as saying: "It's sad. People are saying I need to win for the sport, but I can't do it by myself.

"It's a responsibility of all the athletes to take it upon themselves to save the sport and go forwards without drug cheats."

Bolt will feature on the opening day of the meeting, which gets underway on Saturday.