IAAF president Sebastian Coe insists rogue coaches and agents must be rooted out of athletics if the sport is to rid itself of the stench of doping.

The former Olympic champion was forced to exile long-time friend Alberto Salazar this week in the wake of a detailed report from the US Anti-Doping Agency that unveiled countless doping malpractices within the Nike-backed Oregon Project.

Illicit substances have been a stain and prescription medication muddies the waters, but while there is no proof presently that Salazar pushed the athletes he coached to cross a line, there have been enough instances of others who have been found culpable, with agents similarly becoming persons of interest in the clean-up operation.

“I’ve never thought that athletes who choose to step outside the boundaries are sitting there making unilateral decisions at 3am when they’re a bit bored of finishing fifth and want to get on to the rostrum,” Coe told The Herald. “That’s probably a driving motivation but the way that the sport is structured, there are other influences.”

A troubling pattern, he knows, emerged long ago.

“If you went back into all the high-profile doping offences and found out what the influences were at the age of 15 or 16, I think you’ll find that they weren’t in the best environment.”

Salazar apart, Christian Coleman, has inflicted most reputational damage during these world championships with the 100 metres gold medallist seemingly nonchalant about the drugs testing process. That must change, Coe said.

“I think you’ll find he’ll take a slightly different view, going forward, about the important of whereabouts.”

Yet amid the dark, there has been light, he added, with Dina Asher-Smith's 200m gold which has thrust her beyond the domestic limelight and on to the global stage which could reap huge riches if she triumphs again at the Tokyo Olympics.

“She is going into the next season as the poster-child of our Games next year,” Coe said. “I cannot think of anybody else who will so easily fit that bill. She will have to be buried away in training and get that balance. She has a heightened awareness of what she can do in the sport. We have chatted about that on various occasions. I hope for her own self she is a little bit selfish. She will figure it out, she is smart.”