Kentucky Derby winner Medina Spirit was treated with an antifungal ointment containing the steroid betamethasone that led to the horse to fail a postrace drug test, trainer Bob Baffert said Tuesday.

Baffert said the horse tested positive for 21 picograms of the substance, which is generally awarded to horses therapeutically to assist their joints and is a violation even in a trace quantity on race day at Kentucky.

Regardless of the motive, Medina Spirit will be disqualified from the Derby in case a second round of testing shows the presence of betamethasone. Derby runner-up Mandaloun will be elevated to winner. It is unknown how long Kentucky officials will have to determine whether the outcomes of this Derby must stand or will alter.

“I had been advised that one of the substances in [the ointment] Otomax is betamethasone. While we don’t know definitively that this was the origin of the alleged 21 picograms discovered in Medina Spirit’s post-race blood sample, and our investigation is continuing, I have been told by equine pharmacology experts that this may explain the test results,” Baffert said in the announcement.

“Therefore, I wished to be forthright about this fact once I learned of this info. As I have stated, my evaluation is ongoing and we don’t know for sure if this compound was the cause of the test results or when the evaluation results are accurate, as they’ve yet to be confirmed from the split sample. But again, I have been told that a finding of a small amount, like 21 picograms, can be consistent with application of the type of ointment.

“I intend to continue to investigate and I will continue to become transparent. Meanwhile, I want to reiterate two points I made when this matter originally came to light. FirstI had no comprehension of how betamethasone could have maybe found its way into Medina Spirit (until now), which hasn’t been a case of attempting to match the system or find an unfair advantage. Secondly, horse racing must address its regulatory problem in regards to substances which can innocuously make their way to a horse’s system at the picogram (which is a trillionth of a gram) degree. Medina Spirit earned his Kentucky Derby win, and my pharmacologists have informed me 21 picograms of betamethasone would have had no effect on the results of the race.

“Medina Spirit is a deserved champion and I will continue to struggle for him.”

That milestone win is currently in jeopardy after Baffert’s announcement Sunday that evaluation results demonstrated the horse had the steroid betamethasone in his system. In August a new benchmark has been passed that any detectable quantity of betamethasone in race testing is a breach. Betamethasone is legal under Kentucky racing principles, though it must be rid 14 days before a horse races.

Baffert’s lawyer, Craig Robertson, announced after Tuesday that an agreement was reached for Medina Spirit to operate in the Preakness on Saturday after Bob Baffert consented to prerace blood testing, tracking and medical evaluation. Baffert isn’t attending the raceas he stated he doesn’t want to become a distraction.

Medina Spirit’s failed drug test is that the fifth largest medication violation in the previous 13 weeks for Baffert, a two-time Triple Crown-winning coach and the surface of the sport.