The Brazilian, considered by many to be the greatest fighter in MMA history, defeated Nick Diaz on 31 January after spending a year away from the sport recovering from a broken leg.
The UFC announced earlier today that he tested positive for anabolic steroids, however, Silva's doctor Marcio Tannure says the fighter did not take those substances and will demand follow up tests.
Tannure said: "Anderson told me he's disappointed, upset because he didn't use steroids. He will ask for the confirmation test because he believes the only explanation is a contamination or a mistake from the lab. He told me: 'I have an impeccable career history and I wouldn't want to tarnish my image.'"
He added:"It's too soon to judge. He has the right to a confirmation test and two other results. The Nevada Athletic Commission hasn't talked yet, and the press is already judging him. The process isn't over yet. If the whole process was already over, he would have already been suspended."
The same statement that revealed Silva's positive test, also announced that the defeated Diaz had tested positive for marijuana.