Sir Mo Farah has faced increased scrutiny after a BBC Panorama programme revealed the four-time Olympic champion changed his account over reportedly receiving injections of the legal supplement L-carnitine when questioned by United States Anti-Doping Agency investigators.

The Federal Bureau of Investigation (FBI) is investigating the role of FIFA President Sepp Blatter in a $100 million (£66 million/€92 million) bribes scandal after he appeared to be implicated by his predecessor João Havelange in a BBC Panorama documentary.

UK Athletics has received the initial findings of the group it set up to investigate links with the Nike Oregon Project, and has announced that there is no evidence of any wrongdoing by Britain's double Olympic and world 5,000 and 10,000 metres champion Mo Farah or in the input to his training regime there.

Mo Farah has insisted he will continue to work with Alberto Salazar after accepting the response his coach has made to allegations of doping offences raised by a BBC Panorama documentary earlier this month.

Alberto Salazar has responded to allegations made earlier this month in a BBC Panorama documentary that he violated anti-doping rules in his coaching of several athletes within the Nike Oregon Project, most notably Galen Rupp, the Olympic 10,000 metres silver medallist, has issued his long-awaited riposte in the form of a 12,000 word open letter.

Mo Farah, whose coach Alberto Salazar was alleged to have engaged in past doping violations involving other athletes in his group by a BBC Panorama programme aired earlier this month, has posted a statement on Facebook insisting he has never taken performance-enhancing drugs, and adding that the last weeks have been “the toughest of my life".

Nike has stepped into the controversy over allegations carried in last night’s BBC Panorama programme that Alberto Salazar and one of the athletes he coaches at the Nike Oregon Project in Portland, Galen Rupp, had been involved in doping violations.

Ceaselessly pursuing the truth, as I tend to do when I have an odd moment, I noticed a tweet today from the Daily Mirror’s chief football writer, the estimable John Cross: “Wonderful to turn over to Andy Murray and see some actual sport. Almost forgotten what it was like.”

Alberto Salazar, coach to Britain’s world and Olympic 5,000 and 10,000 metres  champion Mo Farah, has refuted allegations of anti-doping violations made in a BBC documentary, which implicate Galen Rupp, the United States 10,000m record holder and Olympic silver medallist.