Koundouris in the #47 Supabarn Audi meanwhile stopped, sitting almost broadside to oncoming traffic, though was able to get going and return to the pits.
“Yeah it's not a good feeling and I didn't realise … I think he just came in too hot and hit my rear,” said Koundouris.
“I really don't know where he came from.
“We went past the slower car just before that and I think he's just come over too hot and couldn't pull it up and just piledrived me.
“See what we can salvage – hopefully [we] get back out there.”
It was the second incident of the race the Valmont Racing Mercedes had been involved.
It left the Valmont Racing entry with cosmetic damage, repaired at an early stop with race tape across the passenger-side headlight.
“He bombed it on me and so I got a bad run and I got up pretty much alongside, I was right up at the b-pillar,” Padayachee told Speedcafe.com.
“He's turned, and I can't really disappear at the apex.
“It's a bit unfortunate. Nowhere I could go, I was already committed to the inside.”
Yet to receive the Mercedes back in the garage, Padayachee hopes the damage is repairable and the squad will be able to rejoin the race.