After expressing his desire to fight over NYE Weekend at the UFC’s annual year-end show earlier this week, heavyweight Alistair Overeem has decided to be proactive in the matter in hopes of reassuring the public his testosterone-related stumble was an isolated incident rather than a lifestyle choice.

Overeem took to Twitter again earlier today where he revealed he’d submitted to a voluntary screening as a sign of good faith, also taking aim at divisional champion Junior dos Santos in the process based on the title-holder’s recent statements labeling him as a “fake fighter”.

“I’m doing a drug test today to build confidence with the Nevada State Athletic Commission and because I respect and appreciate the UFC,” wrote Overeem on the social networking site, adding, “And to let Junior know I am a clean fighter. I’m all natural Junior and I am coming for you.”

The 32-year old Dutchman is currently sidelined until December 27 after showing a grossly elevated T:E ratio in his system brought on by a doctor-prescribed anti-inflammatory.