Ex-UK Athletics coach George Skafidas has been banned from sport for life by UK Anti-Doping, which accused him of destroying Bernice Wilson's career.
Greek coach Skafidas admitted nine rule violations, committed in 2011 and 2015.
"He was put into a position of trust, he abused that trust and as a result categorically destroyed a career," said Ukad chief executive Nicole Sapstead.
Sprinter Wilson was banned for four years in 2011 after she tested positive for testosterone and clenbuterol.
The 31-year-old tested positive for clomiphene in an out-of-competition test in February last year but her sanction was reduced to 10 months due to "the substantial assistance" she gave Ukad.
A UK Athletics-licensed coach, Skafidas ran a training group for young athletes in Lincolnshire, but Ukad confirmed the nine violations all related to his conduct with Wilson.