UFC light-heavyweight champion Jon Jones admitted he’s used cocaine in the past, primarily in college, but suggested it was a one-time mistake that led to a recent failed drug test.

The interview, which aired tonight on “FOX Sports Live,” followed news earlier this month that Jones failed a drug test due to cocaine prior to a Jan. 3 title defense.

Jones (21-1 MMA, 15-1 UFC), who ultimately recorded his record eighth light-heavyweight title defense with a decision victory over rival Daniel Cormier (15-1 MMA, 4-1 UFC), was randomly tested a month before the fight. The test, administered on Dec. 4, detected benzoylecgonine, the primary metabolite of cocaine.

The Nevada State Athletic Commission received the results on Dec. 23. However, because benzoylecgonine isn’t banned out of competition by the World Anti-Doping Agency, the commission stated on Jan. 6 it couldn’t halt Jones from competing in the pay-per-view fight. That same day, the UFC and Jones announced the 27-year-old fighter had entered a treatment program and was taking rehabilitation “very seriously,” though his mom later said he left after one night (a claim UFC President Dana White said was “not necessarily the case“).

Jones, who was ultimately fined $25,000 (but not suspended) for violating the UFC’s fighter code of conduct, discussed the series of events with “FOX Sports Live” host Charissa Thompson.

Here are 10 key points to come out of his interview:

Jones said he knew he was going to fail the test once he took it. He said he kept it private and didn’t tell anyone, though “I knew the test would come out positive. … I knew there was nothing I could do about it. I was stressed out about it.” He said he was worried about being suspended or being pulled from UFC 182, but by the time he made it to the official fighter weigh-ins, he figured he may have had actually tested clean and assumed the fight would go on. He said he “has no excuse” for using cocaine and was at a party when he used it. He said a “coward” would try to make excuses, but “I’m not going to do that” and instead said he “messed up.” As far as past cocaine usage, Jones admitted he “had done it before, quite a few times in college and experimented with it. But that’s really it. It was mainly just in college I dabbled in it.” When asked if he’s used other drugs, Jones said he “has done his share of partying” but suggested he rarely used cocaine outside of the times in college and the time before UFC 183. He said he’s “not a cocaine addict by any means or even a frequent user.” He said cocaine is “such a dirty drug.” After learning of the failed test, he said he apologized to White and UFC Chairman and CEO Lorenzo Fertitta, in addition to his family, including two brothers who currently compete in the NFL. He said one of his first calls was to his mom, who “was very supportive.” He wouldn’t comment on whether he’ll take action against the Nevada commission for releasing the results. When asked about tests for performance-enhancing drugs , he flatly denied using any. He said his short rehab stay was because the facility did a 24-hour examination and determined he didn’t need inpatient treatment. However, he said he’s volunteered for weekly drug tests and counseling. He said he was “willing to stay there as long as I needed to be there,” largely at the urging of some people close to him, but was ultimately told he should do outpatient treatment. Jones said he hasn’t given much consideration to how the ordeal affects his image. However “my message to my fans is that I’m sorry” for “letting them down.”

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