Dos Santos, 34, tested positive for a banned diuretic on Aug. 10, which carries a potential one-year suspension under the UFC's anti-doping program. The sanction was reduced, after dos Santos proved the test was caused by a legal tainted supplement.

The suspension is retroactive to the date of dos Santos' failed test, meaning it actually expired in February. Due to several factors in this case, however, the sanctioning process took longer than the suspension itself -- which dos Santos admits is frustrating.

"I am not a cheater," dos Santos tells ESPN. "Since the first day we found out about this, we have cooperated with USADA and done everything they've asked or suggested to prove this was not intentional doping. It's taken a really long time.

"We want to know the real results of fights, but in a case like this, with a diuretic, I think they should have allowed me to continue my life until they proved it was my fault. If they prove that, they can do whatever they want. But if I prove I'm innocent, I'm here for almost nine months, doing nothing with my life. I want to keep fighting for a long time, but I don't have any time to lose."

Dos Santos is one of three Brazilian athletes recently affected by tainted supplements, according to a USADA release on Monday. Although UFC athletes are responsible for any substance in their system, dos Santos' frustration is easy to understand.

He has relied on Dr. Maria Amelia Bogea, a specialist in his native Brazil, to oversee his diet and supplemental intake for years. Under Bogea's supervision, he has primarily obtained his supplements through Farmacia Analitica in Brazil.

Immediately after his failed test, dos Santos submitted multiple supplements to be tested for contamination. Initially, he did not even test any supplements from the Brazilian pharmacy, as he had built a high level of trust with the facility over time.

The Farmacia Analitica supplements were eventually tested, however. In December, USADA confirmed several bottles were in fact contaminated with hydrochlorothiazide. Per USADA's protocols, the agency still needed to obtain and test those specific supplements independently, before moving forward with dos Santos' case. So, even though dos Santos had supplied tainted supplements, his case was still on hold.

"I was happy when those results came back, because I thought it was done," dos Santos said. "They would see it's not my fault and I could resume fighting. But then, they started to say other things, like maybe I could have contaminated them on purpose. I said, 'My God, I'm not a chemist.'

"When they found my supplements were contaminated, it was already four months. Now it's been another four months for them to figure the rest out, and finally find the truth."

Dos Santos' attorney, Ana Guedes, said there were several possible reasons the case took so long. Their decision to not test the Farmacia Analitica supplements right away contributed to the delay. Also, Guedes said USADA ran into some difficulty obtaining the supplements independently.

"It's not a place you can just walk in and buy something off the shelf," Guedes said. "And even after purchase, they had to get the supplements into the U.S. and, as I understand it, there was a holdup getting them cleared by customs. It was a unique case, and the delays were not necessarily anybody's fault.

"This system has to be fair and it has to be applied uniformly. I think Junior was an unintended casualty of trying to keep the sport clean."

Dos Santos (18-3) had been scheduled to face Francis Ngannou at UFC 215 in September, but the UFC was forced to pull him from the event as a result of the failed test. Because of this case and injuries, dos Santos has only fought once in the past two years. He is anxious to get back in the cage, but a specific return date has not been discussed yet.

A longtime advocate of drug testing, dos Santos doesn't believe USADA acted inappropriately in his case, but wonders if the system needs to be re-worked to avoid this type of situation.

"I think USADA needs to consider what substance they find," dos Santos said. "If it is not a very bad drug, they shouldn't pull you from a fight. If they haven't proved it is your fault, they shouldn't pull you.

"If I am guilty, do whatever you want to me. But I knew they wouldn't do that, because I am not a cheater. It's been hard. You are considered guilty before being judged."