LEXINGTON, Ky. — Kentucky horse racing stewards have suspended Brad Cox, trainer of 2021 Kentucky Derby winner Mandaloun, for 10 days with a $500 fine and disqualified colt Warrior’s Charge for a failed postrace drug test after the Stephen Foster Stakes last June at Churchill Downs.

The test found Warrior’s Charge had 2.51 micrograms per milliliter of phenylbutazone in his blood after the Grade 2 race on June 26 in which he finished 3 1/4 lengths behind Maxfield.

Cox, a Louisville native, waived his hearing before the Kentucky Horse Racing Commission board of stewards, which issued the ruling on Sunday. Cox will serve the suspension from May 23-June 1 and forfeit $115,200 in purse money. Wagering will not be affected.

Cox’s colt Mandaloun was elevated to Derby winner in February following the KHRC’s disqualification of now-deceased colt Medina Spirit for a failed postrace drug test. The KHRC suspended Hall of Fame trainer Bob Baffert for 90 days through early June and fined him $7,500 for a series of failed tests by his horses. Baffert is suing Churchill Downs in federal court, seeking to overturn its two-year suspension through mid-2023.

Medina Spirit died in December following a workout at Santa Anita in California. A necropsy found no definitive cause for his death.