Both Erebus Commodores have been disqualified from Saturday's ARMOR ALL Top Ten Shootout in Bathurst.
Brodie Kostecki and Will Brown set the fourth and fifth quickest times in the shootout.
However, it was determined, after an investigation, that both cars were underweight.
The team admitted to the breach; Brown/Jack Perkins will start ninth and Kostecki/David Russell 10th for Sunday's Repco Bathurst 1000.
The stewards’ report reads: "After the Session the DRD received a report from the HoM that during Parc Ferme the doors on Car #9, Will Brown/Jack Perkins, and on Car #99, Brodie Kostecki/David Russell, were weighed by Supercars Technical personnel and the left front, left rear and right rear doors on Car #9 ,and the right rear door on Car #99, were found to be under the minimum weight for each such door prescribed by the VSD for the 2021 ZB Commodore in breach of Rule C2.1.1.
"Following a Hearing, the Stewards disqualified both Car #9 and Car #99 from the TTSO."
"Erebus Motorsport is disappointed to hear news that after being reviewed by the Stewards at Bathurst today, they have been disqualified from this afternoon’s Top Ten Shootout," an Erebus statement reads.
"After thorough inspection it was found that although the overall car weights were by the book, doors on both Erebus Holdens were underweight.
"It is a small oversight and honest mistake by the crew who have worked tirelessly for six weeks to ensure they represented the team, its partners, and their fans well.
"Erebus Motorsport apologises and look forward to putting their best foot forward in tomorrow’s Great Race.
"Brodie Kostecki and Will Brown’s Commodores will start from 9th and 10th respectively.
"The team will be making no further comment."
The 161-lap Repco Bathurst 1000 will commence at 12:15pm AEDT on Sunday.
Supercars will return to the track on Sunday for the Warm Up at 9:10am 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.