Scott Pye has revealed the ordeal he went through prior to putting in one of the drives of the race at the Coates Hire Newcastle 500.
The Walkinshaw Andretti United driver stormed from the rear of the grid to sixth despite spending Friday night in hospital.
Having competed in opening practice, Pye was then taken to a local private hospital where he remained overnight, his seat in Practice 2 filled by his Pirtek Enduro Cup co-driver Warren Luff.
“I had gastro, some kind of viral infection, so it knocked me about a bit,” Pye told Speedcafe.com.
“Yesterday I had a really bad fever. I was curled up shaking at the track here, and they decided my temp was too high and I need to go to hospital.
“I knew that if I could get my hydration back then I could be fine,” he added.
“I was a little concerned because I hadn't eaten in 48 hours. I've had a little bit of lunch, which was some Cruskits, and that's it since Thursday – and I've thrown every meal I've eaten up since then.
“I was a little worried about that, but the medical staff did such an amazing job, Dr Carl (Le, Supercars medical delegate) and staff here in Newcastle as well – actually, last night I stayed overnight at the hospital, they were amazing.
“Obviously such a tough race, 250km, both days as well, so it's important to make sure that's right and I was confident enough to go into the race.
“Thanks to those guys a lot, and (it) felt great doing the race, and I was able to push right through to the flag.”
Returning on Saturday morning, Pye was cleared by medical staff to take part in Armor All Qualifying, only to crash out and start the 95 lap race from the back of the field.
His performance included a series of bold overtakes at Turn 8, the right hander between Zaara and Scott Streets, in a race that lasted nearly two hours.
“We just had quite a good car, on its nose, so I was able to get down the inside and have confidence through the turns,” Pye explained.
“We had good speed, so when you're catching them as quick as we were, they kind of could see we were coming.
“We all tend to pick our battles at times, and I think we had a fast car and people could see that.
“I would do a fake, and then I'd see them leave the door open, so then the next lap then I would just go for it.
“Hopefully we got the same tomorrow and we can obviously not stick it in the fence in qualifying and stick it up the front would be nice.”
After three seasons with Walkinshaw Andretti United, Sunday will mark Pye's final race with the team before he joins an expanding Team 18 alongside Mark Winterbottom next year.