American sportswear giant Nike on Thursday reiterated its leading coach Alberto Salazar's refutation of doping allegations made in a BBC documentary.
"We take the allegations very seriously as Nike does not condone the use of performance-enhancing drugs in any manner," Nike said in a statement. "Both Alberto and Galen (Rupp) have made their perspectives clear and fully refute the allegations made against them."
The documentary, broadcast on Wednesday, alleged that Salazar, 56, had encouraged athletes including America's Olympic 10,000 metres silver medallist, Galen Rupp, to use illegal substances.
Both Salazar, who runs Nike's Oregon Project training centre, and Rupp strongly deny all allegations of wrongdoing and none of the athletes from the project has ever failed a drug test.
Salazar also coaches British double Olympic champion Mo Farah, but there is no suggestion Farah broke doping rules and he said he had never taken banned substances or been encouraged to do so by Salazar.
However, European 10,000 metres champion Jo Pavey has told Farah, her Great Britain team-mate, that she would drop Salazar if she was in his position.
"As an athlete, you don't want to associate yourself with people that have got accusations and allegations against them," Pavey told Radio 4. "I'm not here to accuse anyone, but if there was anybody I was slightly associated with that I suddenly realised had these accusations against them -- or any of my training partners -- I'd run a mile."
The investigation by the Panorama programme centred on the Nike running camp in Portland, Oregon, where Salazar is the head coach.
Steve Magness, who worked as an assistant to Salazar at the Oregon Project in 2011, said he had seen a document showing Rupp's blood chart, which revealed that he had taken prohibited testosterone medication as a teenager.
David Howman, chief executive of the World Anti-doping Agency (WADA), said he believed the documentary's claims warranted scrutiny. "I would be not only disturbed, I would be very disappointed and that's why I think it needs to be scrutinised by us as an independent body," he said.
Farah, the Olympic 5,000 and 10,000 metres champion, is scheduled to compete in the Birmingham Diamond League event on Sunday and is due to speak at a press conference on Saturday. Journalists had been told they would be able to interview Farah and other British athletes on Friday, but in an email sent out out on Thursday, organisers said that he would now address the press alone a day later.