Regulators provisionally suspend trainer McLean Robertson

Trainer McLean Robertson has been provisionally suspended by the Horseracing Integrity and Welfare Unit after a horse in his barn allegedly tested positive for a banned substance.

Johnny Up, a 5-year-old Majesticperfection gelding he trains for owner-breeder John Mentz, won a $7,500 claiming race for non-winners of two races lifetime at Canterbury Park on June 4. According to an entry added to the HIWU database of pending anti-doping and medication control violation matters Monday, the horse tested positive for the banned substance altrenogest.

According to the Horseracing Integrity and Safety Authority list of banned substances, altrenogest is an estrus suppression drug. It is used in intact fillies or mares to hold back or regulate their menstrual cycle, in effect delaying or keeping them out of heat. HISA bans altrenogest for intact males, geldings and female horses who have been spayed. For intact fillies or mares, altrenogest is on the controlled list.

McLean Robertson has won 30 of 146 starts this year at Oaklawn, Keeneland, and Canterbury. With 13 wins at the current Canterbury meet, he is second in the training standings, two wins behind Joel Berndt. Stewards scratched both horses Robertson had entered at Canterbury on Monday.

In a training career that dates to 1994, Robertson had 1,544 wins from 7,108 starts as of Monday, with three graded-stakes wins and more than $42 million in purses. He works closely with his father, Grade 1-winning trainer Hugh Robertson, who has been based at Fair Grounds and Hawthorne this year. Horses often move back and forth between their two barns for the same owners.