British Athletics performance director Neil Black has admitted that he would not be able to do his job if he had any doubts over whether an athlete was "clean".
The topic of doping has threatened to overshadow the World Athletics Championships in Beijing, with Mo Farah's coach Alberto Salazar finding himself at the centre of a BBC Panorama documentary and in a separate case, "adverse findings" being discovered in tests conducted as long as a decade ago.
However, Black has insisted that he has no doubts about his team, who will begin their attempt to better their record of three golds and three bronzes from the last staging of the event in Moscow in 2013 on Saturday.
Asked if he believes that British athletics was totally clean, Black told BT Sport: "I couldn't do my job or look people in the eye, I couldn't perform the role of assisting people with their performance unless I believed that.
"So I'm as absolutely confident as I can be sitting here that that is the case."
Black has been in his current role since September 2012.
