The boxer now returns home after admitting to taking a supplement which he claims caused the positive result
Michael Carruth has defended Michael O'Reilly saying that the public and media shouldn't "throw him under the bus" following a positive drug test prior to the Olympic Games.
Speaking on The Pat Kenny Show, Olympic gold medallist Carruth did concede that boxers should know what they're putting in their systems.
"To be the first ever, it might follow him around for a while," he said. "He'll get great support through the Irish Amateur Boxing Association (IABA) and from the Olympic Council as well. He's made a mistake, let's not throw him under the bus.
"He's admitted that the source that has provided him with this supplement is not through the IABA or through Sport Ireland or anybody like that. It's a source that he's not divulging himself.
"We have the fifth most tested sport in Ireland so they're well educated in what they can and what they cannot take. There's enough good people around him that if he had any doubts taking something that they'd be able to contact someone at any notice [sic]. It is a big, big mistake on his part because he knows the fundamentals."
He was then asked if he could put himself in O'Reilly's shoes and imagine what it was like to come home in such a fashion.
"I honestly couldn't. There's going to be an embarrassment part of it, a shame part of it as well and an angry part of it at himself as to why he did it. Every emotion he's going to go through on that plane.
"This won't go away today or tomorrow, people are going to remember this. It's not the nicest way to come home from an Olympic Games. It's a mistake and we just have to make sure that it doesn't happen again."