Apprentice Tom Sadler has been grilled over his handling of Supreme Warrior at Sandown on Wednesday, with a senior steward asking him if he had stopped the horse.
Sadler's ride prompted steward Robert Montgomery to ask him directly: "Was the horse trying?"
To which Sadler replied: "Are you serious?"
Montgomery confirmed the seriousness of the question and Sadler replied: "Yes, I was trying on the horse."
The stewards are concerned with Sadler's performance from the start to the finish of the 1200m race, but have particular concerns about his efforts in the home straight.
Supreme Warrior started at $11 in the Le Pine Funerals Handicap and came from second last in the 16-horse field to finish eighth.
No charge has been laid and the horse's trainer Leon Corstens is yet to be questioned.
The inquiry has been adjourned to a date to be fixed.