Will Brown initially surprised himself when he clocked the quickest lap of the weekend to score Bathurst provisional pole.
Brown emerged atop a trio of drivers in the 2:03s bracket after Friday's enthralling 40-minute qualifying session.
The Erebus Motorsport driver will be last driver out in Saturday's ARMOR ALL Top Ten Shootout.
The 23-year-old clocked his eventual session-topping 2:03.898s some minutes before the end of the session.
Brown was in the Erebus garage once the session ended, making for raucous scenes of celebration.
With Brodie Kostecki sixth, the Shaw and Partners Foundation donated $50,000 to the Erebus squad's charity partner Feel the Magic.
Anton De Pasquale and Chaz Mostert both came within inches of unseating the #9 Shaw and Partners Commodore.
“It took me a second; I was looking at the last number for a two or something, and I saw an eight,” Brown said.
“I thought that wasn’t very good, I thought I did a 2:04.8.
“It took me a second and I worked it out. I probably then wasn’t worried where I’d end up.
“I thought a 2:03 around here was pretty cool. I was happy and I knew it’d put us in the shootout.
“It's cool to be the number one man. We’ll see what happens tomorrow.”
Brown denied Shell V-Power Racing team ace De Pasquale, who has claimed 11 poles in 2021.
De Pasquale managed to secure his place in the one-lap dash at the death, but was pleased he and his team finally managed to find speed in the #11 Mustang.
“Pretty stressful lap to get into the threes,” De Pasquale said.
“We can sleep well and worry about tomorrow and do it again.
“It’s a pretty cool lap around here wherever you end up.
“It’s the most fun session of the year, having this place to yourself.”
Just 0.078s from provisional pole was Mostert, who was delighted to continue his car's strong run at Mount Panorama.
The #25 Mobil 1 Appliances Online Commodore has been in the top three in all sessions so far.
“The car obviously rolled out of the truck pretty good,” Mostert said.
“We’ve done some tuning during sessions and the car is reactive to changes, which is fantastic.
“The guys have done a fantastic job."
Supercars will return to the track on Saturday for Practice 5 at 10:15am AEDT. Click here to view the track schedule.
Every session of the event will be broadcast live on Foxtel (Fox Sports 503) and streamed on Kayo.
The Seven Network will provide live free to air coverage of the event. Tickets for the event are on sale now.