IAAF president Lord Coe insists athletes' reputations should not be tarnished by association with Alberto Salazar.

The American coach was earlier this week given a four-year ban for doping violations.

Salazar was sanctioned along with endocrinologist Jeffrey Brown for "orchestrating and facilitating prohibited doping conduct" while working with the Nike Oregon Project, the United States Anti-Doping Agency said.

Great Britain's four-time Olympic champion Mo Farah worked with Salazar from 2011 until 2017.

Farah, who is not accused of any wrongdoing, said in a statement on Tuesday he had no tolerance for anyone who breaks the rules.

NOP athlete Donavan Brazier won the men's 800 metres at the World Championships in Doha on Tuesday, while new 10,000m champion Sifan Hassan – who is coached by Salazar – will compete against Britain's Laura Muir in the women's 1500m. Neither athlete is accused of any wrongdoing.

And Coe is adamant that athletes should not be condemned for links to Salazar.

"No, no. I'm sorry, I don't live in that world where you just automatically assume the worst," he said, speaking to the PA news agency in Qatar.

"The reality of it is, the charges that have been laid by USADA are serious.

"The AIU (Athletics Integrity Unit) was reaching out to all those athletes and a banned coach has to sever relationships with those athletes.

"That's what's taking place. Coaches and athletes have to make judgements all the time.

"If you are coached by somebody, you should be absolutely comfortable you are working in an environment that's safe and secure and is not going to damage you own reputation.

"Mo is an outstanding athlete and I get asked the question regularly, 'Should this athlete be with this coach?'

"If they remain with those coaches, you have to presume they have had those questions satisfactorily answered."

Salazar had his accreditation stripped by the IAAF, meaning he could have no contact with his athletes.

And Coe insists the championships, which had already come in for criticism for poor crowds and intense heat, have not been heavily impacted by news of the 61-year-old's ban.

"It's what happens. The media teams dealt with it. We're dealing with it," he said.

"It doesn't derail the Championship. It may for you guys (the media), but in reality it's not a broader issue for most people watching the Championships.

"We've got the systems in place to deal with that now. If that would've happened five or 10 years ago, people would've been looking at each other and wondering what we were doing.

"Within minutes of that, we knew what the process was."