Brett Okamoto of ESPN.com reported the news Tuesday, noting the B sample was for Jones' failed drug test from July 28. According to Okamoto, the United States Anti-Doping Agency (USADA) in August told Jones he tested positive for the anabolic steroid Turinabol on July 28.
This comes after Ariel Helwani of MMA Fighting reported on Sept. 1 Jones passed a blood test in the immediate aftermath of UFC 214 on July 29. Helwani also noted Jones passed tests on July 6 and July 7, although his July 28 urine test came back positive.
Jones reclaimed the UFC light heavyweight title after defeating Daniel Cormier at UFC 214 via third-round knockout.
On Aug. 22, the UFC released a statement revealing it was told of Jones' positive test that was collected after his weigh-in for the fight against Cormier. "Under the UFC Anti-Doping Policy, there is a full and fair legal process that is afforded to all athletes before any sanctions are imposed," the statement read in part.
Shaun Al-Shatti of MMA Fighting noted this is not the first issue for Jones, who was stripped of his previous title following a hit-and-run accident and lost the UFC interim light heavyweight title when he tested positive for two banned substances before a scheduled fight against Cormier.
As for Tuesday's news, Okamoto explained B samples rarely negate positive tests and granted "Jones' investigation into the possibility of tainted supplements is most important to his defense at this time" since the fighter is denying taking the banned substance knowingly.
According to Okamoto, the UFC hasn't yet stripped Jones of the title he won against Cormier, but the result will likely be changed to a no-contest. He could face a suspension of up to four years for a second anti-doping program offense.