The chassis in question is the ZB Commodore which was already been rebuilt in recent weeks after a 56 g hit in the previous event of the season at Pukekohe.
It is not known if it will return in time for Qualifying in about 90 minutes from now, but is unlikely to be a scratching from the Great Race.
Brown put his hand up for the incident, saying he hit the wet edge line.
“I screwed up,” he admitted.
“There's no better way to put it; it was completely my fault.
“I was actually running really good, didn't feel like I was risking anything, but just tapped that white line with the left-rear and then lock the front and I was in.
“Luckily, I think it rode the berm a little bit around the side and it's done two corners, but no actual chassis damage from what we can see here.
“This poor old car doesn't need any more chassis damage; she's had a hard life.
“So hopefully, we can just put some wheels on it and I can drive safe I the next one.
He added, “We've got a lot of work to do before qualifying.
“Who knows if it'll be back out for qualifying but we'll definitely be back out tomorrow, so we'll be trying our hardest.”
Brown, who is sharing his Boost Mobile-backed car with Jack Perkins, was fifth-fastest for the session.
Qualifying had been scheduled to start at 16:15 local time/AEDT although may get underway late given delays caused by weather conditions and associated incidents.