Police have warned revellers against "pre-loading" - getting drunk before going out - saying they will be turned away from events if they are under the influence.
The warning came after two 19-year-old women ended up in the cells because they were too drunk to get into the races in Hawkes Bay last weekend.
Senior Sergeant Freddy van Duuren said the women and two male friends tried to get into the racecourse when it opened at 11am but were denied entry because they were "very, very drunk".
Their male friends disowned them so the women, who could barely stand, were taken to the Hastings station for detox.
It was not known what time the girls had started drinking, but it was likely to have been early, Mr van Duuren said.
More examples of pre-loading were obvious as the day. A steady stream of people turned up at the racecourse gates "well and truly loaded" and were also turned away.
"Pre-loading is a major issue not just for police - it has flow-on effects to event organisers, bar staff, hospitals and other members of the public. If you're going to have a few drinks before going out, keep it to a few and don't write yourself off. You run a very high chance of being denied entry to an event or a bar if you turn up at the door already intoxicated.
"What's the point?" Mr van Duuren said.
With a long list of events lined up for this summer, event organisers would be encouraged to deny entry to anyone who showed obvious signs of intoxication, regardless of whether they have pre-bought tickets.
"Buying a ticket to an event does not give you automatic entry. Many events now have terms and conditions written on the ticket that state intoxicated patrons will not be allowed entry. So it's pointless turning up drunk to something you paid good money to attend and not be allowed in," Mr van Duuren said.