UFC's Nate Diaz accepts USADA warning after openly vaping

UFC veteran Nate Diaz has accepted a public warning by the United States Anti-Doping Agency (USADA) for his admitted use of the banned substance Cannabidiol following UFC 202.

Following a majority decision loss to Conor McGregor on Aug. 20 in Las Vegas, Diaz, 31, openly smoked a vape pen while fielding questions from the media.

When asked what was in the device, Diaz revealed it was "CBD oil," which he said helps in his recovery process. Cannabidiol is considered a banned substance by USADA up to six hours after competition. It is characterized as Cannabinoids.

USADA immediately announced it was investigating Diaz's admitted use of a banned substance.

On Thursday, the anti-doping agency stated Diaz mistakenly believed the timeframe in which Cannabinoids are banned ended immediately after the fight, which is the case under the rules of the Nevada State Athletic Commission.

Additionally, USADA confirmed Diaz passed in-competition blood and urine samples prior to his use of the vape pen. As a result, USADA felt a public warning was appropriate.

Diaz (19-11) has been relatively quiet since UFC 202. He also faces potential sanctions under the NSAC for his role during a prefight news conference, as does McGregor. Diaz, who fights out of Stockton, California, has said the only fight he's interested in is a McGregor trilogy bout.