"It is the only day during the season we charge to get in, and we will not entertain people arriving drunk.
"So, to avoid embarrassment and disappointment, don't pre-load at home first."
Similar restrictions have applied at the recent New Zealand Cup Week at Riccarton and at the Wellington Cup carnivals.
Meanwhile, the annual Repco Mascot race sideshow is shaping up as a real grudge match between extended family members.
"The inaugural mascot race was won by my nephew Matt Field who raced as Turbo Man, mascot of the Manawatu rugby team," Mr Field said.
"He lives in Palmerston North and works for trainer Kevin Gray.
"He has since had a kidney transplant donated by his sister Ruth and won seven medals, including six gold at the Australasian Transplant Games, so he's recovered well.
"He was also named an ambassador for the World Transplant Games in Spain next year.
"I have invited him back to race here and hopefully take the winner of the last two down a peg or two."
Mr Field's stepson Jordan Baldwin, racing as The Beer Baron, has easily won the last two Repco-sponsored events and while substantial prizes are up for grabs, bragging rights too are on offer.
In some quarters Mr Baldwin has lightheartedly been accused of taking the bragging rights a step too far and needed to be put back in his place.
"That's why I've invited Matt back and Jordan is not so confident now," Mr Field said.
The race will be run just after 2pm on Saturday.