Mostert is still a long way from being a household name, but his extraordinary victory in an astonishing race has made him the hottest new name in V8 Supercars.

Although keen followers of V8 racing knew he was an emerging young talent, most of those who watched spellbound as he won from nowhere were as surprised as he was.

With the Ford Performance Racing Falcon he was sharing with veteran Paul Morris starting from last on the 25-car grid – relegated because he made a rule-breaking error in qualifying – Mostert never considered they had a chance of winning.

That he snatched the win late on the very last lap as V8 champion Jamie Whincup ran low on fuel still makes Mostert want to pinch himself.

"It's something that's so unbelievable – I can't really accept the fact that we have won Bathurst," Mostert said.

"It's something I never thought was going to happen, coming off the last row of the grid and all that kind of stuff. It was just unbelievable. It hasn't sunk in. I can't even process it."

As he prepared for this weekend's twin-race Gold Coast 600 at the Surfers Paradise street circuit, Mostert remained almost incredulous that amid the day-long drama at Mount Panorama, he found himself contending in the chaotic closing stages.

"Going into the race, I never had the mindset to try to win," he said.

"It was to try to get to the top 10 and if we made it there, then we'd had a really good day. The main focus was just to finish on the lead lap and build experience for years to come."

The race was stopped for more than an hour after 61 laps for a section of the resurfaced track to be repaired. More crashes after the resumption turned the remaining 100 laps into a guessing game.

Throughout the event that has a history of interruptions, teams juggled pit stops around the record-equalling 10 safety car interventions that were triggered by all the crashes.

Mostert, 22, and Morris, 46, were the odd-couple combination that very few – if anyone – picked to be among the front-runners, much less win.

Their 13 pit stops kept them in the running and the constant top-ups of fuel were ultimately crucial in ensuring that Mostert had enough to race flat-out to the finish – unlike Whincup and others – after the last, late safety car.

"I was thinking I might be able to get a podium, which would have been an absolutely fantastic story after starting from the back of the grid, but even at that stage, I wasn't thinking I had a shot at winning," Mostert said.

"It wasn't until maybe the last 10 laps that I thought I was in with a chance, but I also thought that Jamie was going to have luck on his side and he was going to get there.

"I never knew that in the last two laps he was going to slow a lot and come back to me. I just kept pushing on and then it really only sunk in about 200 metres past the finish line, which is pretty crazy."

Going into the last lap, Mostert's Pepsi Max Crew Falcon was glued to the tail of Whincup, who was defending furiously as he desperately – and belatedly – backed off to conserve what little fuel remained in his Red Bull Racing Holden Commodore.

Mostert remembered being focused more on overtaking Whincup than the big prize that awaited.

"I was just so full of adrenalin and I just wanted to get past him," he said. "I wasn't really even thinking that if I passed him, I'm going to win the Bathurst 1000. I didn't even have time to think about that.

"I was just doing everything I could to get past him. In the last couple of corners, I wasn't really celebrating that I was going to win the Bathurst 1000; I was celebrating that I just got past Jamie Whincup. How cool's that?

"There was just so much stuff to take in and, unfortunately, I didn't have the biggest brain in the world to work everything out."

Mostert, from Melbourne, is now aiming to finish his sophomore season in V8 Supercars – and first year with the factory-backed FPR squad – by finishing in the top five of the championship.

After struggling in the first half of the season, he has come on strong with eight podium finishes. His career-defining Bathurst victory – his second race win this year and third in two years – lifted him to seventh in the title standings, just 102 points behind James Courtney and Shane van Gisbergen, who are tied for fourth.

"I never thought I'd have a year like this," Mostert said. "It's been fantastic."

Mostert and Morris are also out to win the Enduro Cup title, awarded to the combination that scores the most points in the Sandown, Bathurst and Gold Coast long-distance races.

They are second to Whincup and Paul Dumbrell, trailing by just 30 points as they go into the deciding pair of 300 kilometre races on the treacherous Surfers circuit on Saturday and Sunday.