Rain caused chaos in race one of the Hamilton 400 V8 Supercar event, with several collisions on and off the track as Rick Kelly led an all-Holden podium finish.
The slippery concrete in pit lane caused Shane Van Gisbergen to overshoot early on, hitting a cameraman - he was okay but the New Zealand driver lost lots of time despite starting in fourth, while pole sitter Jamie Whincup hit a wall in pit lane and also fell back.
There was more carnage on the Hamilton streets but the 59 laps ended with a Holden 1-2-3, two-time Bathurst winner Kelly - who started in third position on the grid - getting the win ahead of Craig Lowndes and his brother Todd Kelly.
It was Kelly Racing's first victory in their third season as a V8 Supercar outfit.
Fabien Coulthard was top New Zealander in eighth with Greg Murphy just behind him in ninth and Van Gisbergen ending in 16th.
St John says seven people needed to be taken to hospital from the Hamilton event, and 61 patients in all were treated by the service.
This is up from 44 who were treated Friday for minor medical and accident cases.
St John says spectators need to wear suitable footwear because of the wet conditions.
