Aidan O'Brien was fined 2000 euros, Wayne Lordan banned for five days and horse Music Box suspended for 42 days at Dundalk on Friday evening.
A 14-1 chance, Music Box was making her debut in the Dundalk Stadium - Light Up Your Night Maiden when staying on strongly for third, a length away from winning stablemate Asking.
However, the stewards inquired into the running and riding of the Invincible Spirit filly, with evidence heard from Lordan and O'Brien's representative Pat Keating, who according to the official report " expressed his satisfaction with the ride and furthermore was delighted with the animal's run".
Music Box was short of room over a furlong out and switched right inside the final furlong, and the report went on: "It was put to Lordan that there was plenty of room to challenge along the rails but while accepting that fact, he stated that he felt that his mount might react to having only a running rail on her inside and therefore was satisfied to move outwards to challenge between horses. He added that the filly was straight enough in her fitness but was having her first run as against all the other runners that had past experience."
The stewards also received a report from the Turf Club Veterinary Officer who stated that Music Box had given a couple of coughs and had a slight nasal discharge possibly as a result of kickback during the race.
Having viewed the recording of the race and considered the evidence, the stewards were of the opinion O'Brien and Lordan were in breach of Rule 212 (A) (ii) & (iii). Lordan was also ordered to forfeit his riding fee.
O'Brien later had another win on the card, courtesy of Royal Lodge Stakes runner-up The Anvil in theDundalk Stadium Business Club Maiden over an extended 10 furlongs.
Sent off the 30-100 favourite, Donnacha O'Brien's mount accounted for Mauricio by five and a half lengths.