Mo Farah has been warned by a tearful former team-mate that more revelations about Alberto Salazar are in the pipeline and he risks tarnishing his reputation if he stays with his coach. On a day when Farah pledged to talk under oath if the United States Anti-Doping Agency questions him about the Nike Oregon Project, Kara Goucher, who trained alongside him in 2011 and 2012, urged anyone thinking of training with Salazar to "think long and hard because you're going to be labelled something for the rest of your life".

Goucher's claims came a day after it was revealed Usada's team of detectives, who brought down Lance Armstrong in 2012, have put their investigations into Salazar and Farah's training partner Galen Rupp on a more formal footing by interviewing the Oregon Project athlete Treniere Moser.

Last night Salazar promised to co-operate with Usada if it decides to question him saying: “Absolutely, I’ve got nothing to hide”. However, when asked whether he would go under oath, he said: “I’m don’t understand exactly what that means. I’d need to speak to my lawyer.”

When told it would mean if he lied then he would be in trouble, Salazar repeated: “I would have to speak to my lawyer about that.”

Usada is also expected to speak to other Oregon Project athletes and its investigation could even include senior figures at UK Athletics, which employs Salazar as a consultant. There is no suggestion that Farah has committed any wrongdoing, and he has made it clear to friends he would be happy to speak to any relevant authority, at any time, in any circumstances.

Goucher, the 2007 world championship 10,000m bronze medallist, said “multiple sources” had come forward since the BBC Panorama’s documentary aired at the start of June. In it Goucher alleged Salazar had coached Rupp to try to get a Therapeutic Use Exemption for an intravenous drip before the 2011 world championships and had offered her a thyroid drug to get her to lose weight.

In his 11,750-word response to the BBC’s claims last week Salazar called both claims false and published detailed email documentary that appeared to show he was happy with Goucher’s weight.

Yet Goucher stands by her story and is still working with Usada. “I have, constantly, all day long, people passing me information, wanting me to bring it forward,” she said. “I really want to encourage all the people who have reached out to me to reach out to Usada, to please come forward. I pass everything along that you give me but the case is much stronger if it comes from you.

“I will most definitely give all my evidence in the coming days. They took my quotes out of context and when you put partial emails or emails from a 10-email-long chain and just put one in, you don’t get both sides. I understand that, if you read it through, it looks like I’m a liar. I don’t like being labelled a liar, just like anybody else.”

Goucher insisted she would continue to fight for a clean sport despite Salazar’s counterattack. “I’m being dragged through the mud and it will probably continue but I’m still here, I’m going to keep racing and I stand by my statements and I always will.

“I want my son to be able to believe in the sport and the system, I want Usada to show they work and I want justice for everyone involved. I want people to like me but my love for the sport is much stronger than my passion that people like me.”

Goucher, who first spoke to Usada in February 2013, added she had spoken to Usada “very recently” and would welcome the opportunity to go under oath. “I would welcome that opportunity for myself, for every former Oregon Project member, for every doctor that’s been involved,” she said.

“I believe in the truth, and I know that these things take time. I believe that Usada is doing everything in their power. Think of how long it took for Lance. I believe the truth will come out. When? I don’t know.”

Matthew Centrowitz, who won the 1500m at the US trials on Saturday, insisted he had never seen any evidence of wrongdoing at the Nike Oregon Project.

He said: “I can safely say that if I ever saw one thing that I felt was wrong or whatever I would be the first to leave. I’ve been part of the group since the Olympics and on and I have never seen anything from Alberto, Galen or anyone on our team or staff do anything wrong.

“For the record I am not currently on TUEs, I don’t take inhalers. I am not on thyroid medication, never have, never been. And honestly the only supplements I take are vitamin C, iron and B. There is a life after running and I don’t plan on jeopardising that.”

Centrowitz said Usada had not approached him but promised be would be willing to talk if they did.

“They haven’t approached me but if they do, I’ll be arms open, willing to discuss and talk about whatever they need from me.”

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