Jamie Whincup has botched a huge opportunity to close the gap on Supercars leader Scott McLaughlin in qualifying at Symmons Plains.
The 12-time race winner in Tasmania locked his brakes heading into the circuit's infamous hairpin, drawing a red flag and the mandatory penalty of starting from the back of the grid.
"Small error and costly mistake," the Red Bull Holden Racing Team man said, shaking his head in pit lane.
Whincup, second in the series standings, was poised to make up crucial ground on McLaughlin this weekend.
He has nine more race wins than any other driver in the field at a circuit that Commodores have dominated in recent years.