Longtime UFC middleweight champion Anderson “The Spider” Silva had a disastrous return to the sport earlier this year.

The 40 year old Brazilian MMA legend, who had not fought since suffering a horrific knee injury in a bout against Chris Weidman in 2013, won his bout with Nick Diaz — but tested positive for banned substances. He now faces both a tarnished reputation and a lengthy suspension, along with the result of bout switched to “no contest.”

“The Spider” is known for his good-natured retort, “is normal!” But this scenario is anything but.

However, Silva, who will appear in front of the Nevada Athletic Commission tomorrow, has provided his explanation.

As reported by the Brazilian website Combate, Silva claims he had a supplement and a sexual performance enhancing drug which were contaminated with the banned substance drostanalone.

“The problem with this defense is that, even if accepted, the prohibition on PED’s is absolute and athletes are responsible for what they put into their bodies,” Canadian attorney Erik Magraken wrote on his blog, Combat Sports Law. “Anti Doping violations are a strict liability matter under the Nevada regulatory scheme. In other words, you are liable for the failure even if you really did take a tainted supplement.”

On the other hand, the current system of punishments by Nevada was not in place at the time of the bout. The NAC recently had its lifetime ban of another Brazilian MMA fighter, Wanderlei Silva (no relation), overturned.

Silva’s hearing is scheduled for 11 AM ET, and will be broadcast on UFC Fight Pass.