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

In a statement issued by his lawyer, Baffert said Medina Spirit was treated for dermatitis with the ointment once a day leading up to the May 1 race and that equine pharmacology experts have told him this could explain the test results. Baffert said the horse tested positive for 21 picograms of the substance, which is typically given to horses therapeutically to help their joints and is a violation even at a trace amount on race day in Kentucky.

Regardless of the reason, Medina Spirit would be disqualified from the Derby and Mandaloun named the winner if a second round of testing shows the presence of betamethasone. Preakness officials said Medina Spirit and Baffert’s other horses running at Pimlico Race Course this weekend will be allowed to enter the race, subject to additional testing and monitoring.

“My investigation is continuing, and we do not know for sure if this ointment was the cause of the test results, or if the test results are even accurate, as they have yet to be confirmed by the split sample,” Baffert said. “I have been told that a finding of a small amount, such as 21 picograms, could be consistent with application of this type of ointment.”

Baffert said at a news conference Sunday at Churchill Downs that he did not know how the substance made its way into the colt’s system.

Dr. Mary Scollay, executive director and chief operating officer of the Racing Medication & Testing Consortium, was surprised the situation went from no explanation to “documented, chronic exposure to the medication.”

“We know that the horse was exposed — deliberately exposed — on a daily basis to betamethasone,” Scollay said Tuesday via phone. “So, yes, it is not implausible that this is the source of the betamethasone in the horse.”

Medina Spirit drew the No. 3 post in a field of 10 horses for the Preakness, attempting to win the first two legs of the Triple Crown with a giant asterisk. He is the 5-2 morning line favorite, though actually Medina Spirit getting to the starting gate Saturday is pending additional tests that Maryland Racing chief veterinary officer Dr. Dionne Benson expects back Friday.

As is the case in Kentucky, no level of betamethasone is allowed in a horse’s system going into a race in Maryland, so the presence of it could lead to Medina Spirit being scratched.

Medina Spirit and stablemate Concert Tour arrived at Pimlico Race Course on Monday and jogged on the track Tuesday morning, though Baffert does not plan to be in Baltimore for the race and put assistant Jimmy Barnes in charge.

“It’s been in Ohio as early as the mid-1850s at least, brought in as an ornamental plant because of its unique foliage and white flowers,” Gardner said. “It was actually planted in people’s landscaping, and it has been spreading.”

“Medina Spirit earned his Kentucky Derby win, and my pharmacologists have told me that 21 picograms of betamethasone would have had no effect on the outcome of the race,” Baffert said. “Medina Spirit is a deserved champion, and I will continue to fight for him.”

Medina Spirit’s failed drug test is the fifth medication violation in the past 13 months for Baffert, a two-time Triple Crown-winning trainer and the face of the sport. Winning the Preakness with either Medina Spirit or Concert Tour would give Baffert a record eighth victory in that race, breaking a tie with 19th-century trainer R.W. Walden.

Except for 2020, when the Triple Crown races were run out of order, Baffert is undefeated with the Derby winner in the Preakness.