Understanding 'Reversal of Form' in Horse Racing: Definition & Explanation

Question
hello sir, can you please explain me what does REVERSAL OF FORM mean in the below statement? this is one of the raceday reports at our local racetrack.

"The Stewards fined Trainer M.R. Chauhan a sum of Rs. 20,000/- for the reversal of form in respect of his charge KOHINOOR SUPREME (A. ASHHAD ASBAR) the winner of this race as compared to his charge抯 previous runs where he ran off board."

Answer
hi -- reversal of form means to me that the horses racing form changed so drastically that it was taken notice of by all who looked at the race results. if a horse has poor form and then all of a sudden it wins a race when it has proven that it is in poor form, then the red light  goes off and the horse and trainer are looked into to see why the form  changed. thanks ED HESS