Colorado Springs: American sprinter Tyson Gay's former coach has been suspended for eight years for doping violations, the U.S. Anti-Doping Agency said on Wednesday.

An independent arbitration panel found that Jon Drummond possessed, trafficked, and administered banned performance enhancing substances to an athlete under his care as a coach, USADA said on its website.

The former Olympic relay gold medallist and Olympic coach was Gay's coach when the former world champion tested positive in 2013 for a banned substance, according to the arbitration panel decision.

Gay, the U.S. record holder at 100 metres, was suspended for one year in May. He returned the silver medal he won with the U.S. 4x100 metres relay team at the London Olympics and was disqualified from all races he contested from July 2012.

His ban was reduced as the result of testimony he provided to USADA and he has since returned to competition.

"A coach cannot lead an athlete to into the danger of using prohibited substances. . . . A coach must be a watchdog when it comes to prohibited substances," the arbitration panel said.

The suspension bans Drummond, 46, from coaching, training or advising athletes and participating or coaching at any event sanctioned by USA Track & Field and the International Association of Athletics Federations.

Attempts to contact Drummond and his lawyer went unanswered.

Drummond was the U.S. relay coach at the London Olympics and the recent chairman of the USA Track & Field Athletes Advisory Council. He began coaching Gay in 2007, according to court documents.

Drummond earlier this year sued Gay and USADA for defamation, claiming Gay had made false statements about him and that USADA had republished and endorsed them.

A U.S. judge stayed the lawsuit, saying the matter should be settled in arbitration, not federal court.