Team Sky have announced the departure of race coach Bobby Julich after reaffirming their zero-tolerance policy to doping.
American Julich admitted to having taken a banned substance in the late 1990s during his racing career and his two-year spell at the British team has now come to an end.
Team Sky principal Dave Brailsford said: "Bobby has shown courage in admitting to the errors he made long before his time with Team Sky. We understand that this is a difficult step for him and we've done our best to support him.
"We've made clear our commitment to being a clean team and been open about the steps we're taking." - Team Sky
"It's important to emphasise that there have been no doubts about his work with us or his approach as a coach.
"He has done a good job and been a good colleague during his two years with us. Bobby has our best wishes for the future.
"We've made clear our commitment to being a clean team and been open about the steps we're taking.
"Although it's never easy to part, we believe this is the right thing to do."
Julich worked closely with Briton Chris Froome, runner-up in the Tour de France to Bradley Wiggins.
Speaking at the launch of the 100th Tour yesterday, Froome predicted departures from the British team after Brailsford reiterated the zero-tolerance policy to doping in the wake of the Lance Armstrong scandal.
Froome told BBC Sport: "That's going to be part of the losses the team has to make to be able to go forward.
"I wish it was that simple for everybody on the team. (But) we have staff and riders who rode in that time (the Lance Armstrong era)."
Brailsford and sports psychiatrist Dr Steve Peters are in the process of interviewing all riders and members of staff at Team Sky and asking them to sign a statement to confirm they have never been involved in doping.
In an open letter published on www.cyclingnews.com, Julich admitted to use of blood-boosting agent EPO between August 1996 and July 1998.
He wrote: "I knew that it was wrong, but over those two years, the attitude surrounding the use of EPO in the peloton was so casual and accepted that I personally lost perspective of the gravity of the situation."
The intervention of his fiance (now wife) and the 1998 Festina Affair saw Julich turn his back on the use of performance-enhancing drugs.
Julich, who hopes to remain in the sport, wrote about his work with Team Sky and that the zero-tolerance attitude was part of his motivation for joining the British set-up.
"I apologise to everyone, especially those associated with Team Sky for my past indiscretions," he added.
"I made some poor decisions and have paid and will pay a huge price. I am taking responsibility, at the expense of not being able to finish what I started, with some of the best people that I have ever been associated with.
"To this new generation of young riders; I hope that you will learn from the past and avoid the mistakes many of us have made. It is up to your generation to insure that the issues of the past do not affect your future.
"I am truly sorry that you all are dealing with something that you had no part in creating."
Julich placed third in the 1998 Tour de France and began his career at Motorola, where Armstrong was a team-mate.