Diaz returns to the Octagon next month and so the employee for the anti-doping agency was required to turn up at his residence to take tests.
Tests are of course urine samples but while Diaz obliged, it seems he did not give enough and so the USADA man needed a little bit more.
Diaz made him wait, though, and proceeded to smoke lots of marijuana and capture the whole thing on his Instagram live for thousands of people to watch.
“This man won’t get out of my house because I didn’t give him enough piss,” Diaz said on the live.
“I pissed all I can, my n****. How many litres do I do? I’ve got two more litres of piss I’ve got to give him and he won’t get out of here until [then]. DK is my guy but USADA can f****** suck a d***
"Come back in six hours, I’ll give you two more. Sorry DK."
Diaz even offered 'DK' - as the Stockton fighter has christened him - a blunt - but he politely refused the offer.
Diaz is a staunch weed smoker and in January 2021, he will have been delighted to hear UFC had tweaked their policy so that those who tested positive for the herb would not receive a ban.
Jeff Novitzky, UFC's vice president of athlete health and performance, said in a statement: "While we want to continue to prevent athletes from competing under the influence of marijuana, we have learned that blood and/or urine levels of carboxy-THC have little-to-no scientific correlation to impairment.
"THC is fat soluble, meaning that once ingested, it is stored in fatty tissues and organs in the body and can be released back into the blood or urine, sometimes long after ingestion."
However, Novitzky did confirm fighters would not be allowed to be high on fight night.
Diaz is currently on a two-fight losing streak and will be desperate to get back to winning ways when he squares off against the unbeaten Khamzat Chimaev in the UFC 279 main event on September 10.
Featured Image Credit: Image: Nate Diaz
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