Racing Victoria's head of integrity Jamie Stier says if ever a protest is to be upheld for a breach of the whip rules, it would most likely come as the result of a dead-heat.

However, Stier said there was many complexities surrounding those whip rules.

Jockey Billy Egan was suspended for six meetings and fined $1500 after using the whip on nine occasions before the 100m as Plein Ciel shared victory with Shot Of Irish in the Travis Harrison Cup at The Valley.

Stewards have the power to lodge a protest, however one was not lodged on Saturday with the whip breach only discovered following correct weight.

Stier explained there was a steward in the stipes' room at The Valley watching the final stages of the race.

He said, having spoken with stewards, the first time the whip was used by Egan aboard Plein Ciel was at about the 400m mark.

"That it was used that far from home at Moonee Valley wasn't identified," Stier told RSN.

"At tracks where you have a 400-metre straight, that is far more easily identified.

"I'm not going to sit here and justify that. It was missed, simple as that."

While jockeys are fined and suspended for whip breaches, Stier is against disqualification and said it was hard to quantify how much effect the whip has on a horse.

"If a breach has occurred more than 100 metres from the finish, what quantifiable impact that has at the end of the race is not an easy task," Stier said.

"We all see where horses are headed close to home and the rider puts the whip away and resorts to hands and heels riding and the horse surges and comes again.

"It's not clear-cut and each case has to be considered on its merits and you need to look at things in totality."