In an Instagram post Wednesday morning, the 33-year-old stated, "To all my fans, I wanted to be the first to let you know that [the United States Anti-Doping Agency] and [New York State Athletic Commission] have informed me of an adverse finding in a test taken for my last fight. While words can't even begin to express how disappointed I am at this time, please know that I'm working with my team to understand what has occurred and how to resolve this situation as quickly as possible. Out of fairness and respect to the rest of my division, I've informed the UFC that I'll be voluntarily relinquishing my title while I deal with this matter. I want to thank all of you in advance for the support."
An hour after Dillashaw's announcement, ESPN's Ariel Helwani reported that the NYSAC had levied a one-year suspension and $10,000 fine on Dillashaw "for violations relating to use of a prohibited substance." There has been no official announcement by USADA or the UFC, and no additional detail is yet available regarding the nature of Dillashaw's test result.
Dillashaw (16-4) held the bantamweight title since November 2017, when he dethroned Cody Garbrandt via second-round knockout at UFC 217, and defended the title against Garbrandt at UFC 227 last August, that time knocking out his nemesis in the first round. He fought most recently in January at UFC Fight Night 143, where his bid to become a two-division champion by dropping in weight to challenge flyweight champ Henry Cejudo ended in a 32-second knockout loss.