Horse trainer Doug O'Neill

The ban is enforceable under the event's convicted trainers rule, which prohibits trainers who have in the preceding 12 months been found by any racing regulatory agency to have violated rules forbidding the possession or use of any Class 1 or 2 substances.

O’Neill is most famous as the trainer of 2012 Kentucky Derby and Preakness winner I’ll Have Another, who was scratched the day before the Belmont Stakes with an injury and subsequently retired.

This new punishment is the result of a positive test by one of O’Neill’s horses, Argenta, for a higher than allowed level of total carbon dioxide at the Del Mar Race Track.

The ban is enforceable under the event’s convicted trainers rule, which prohibits trainers who have in the preceding 12 months been found by any racing regulatory agency to have violated rules forbidding the possession or use of any Class 1 or 2 substances. According to sources O'Neill has accepted the Breeder’s Cup decision and will not appeal it,”

Under a settlement with the New York Gaming Commission, O’Neill’s suspension begins Nov. 3 — two days after the Breeders’ Cup — and ends Dec. 18. O’Neill had earlier said he wasn’t in New York when the alleged infraction occurred in June 2013 and he’s confident that none of his employees or staff administered the substance to the horse that tested positive.

“I now realize that delaying the suspension so that I could participate in the Breeders’ Cup was a mistake,” O’Neill said Friday.

He said before the Breeders’ Cup ban, he had asked New York officials to move up his suspension so it begins on Monday.

“One of the reasons I wanted to resolve these allegations was to not be a distraction to the racing community,” O’Neill said. “I truly care about the horses under my care and the sport that we all love and do not wish for my suspension to do any more harm than it has already done.”