Craig Lowndes and Mark Winterbottom have suffered setbacks to their Supercars title bid while watching on from the garage at Sandown.

The pair were helpless onlookers as their co-drivers tangled in a bungle during the first turn of the first lap of their qualifying race for the 500km classic.

Paul Dumbrell – partner of series leader Jamie Whincup – raced away to win the session ahead of Prodrive Racing’s Steve Owen.

Their untroubled runs mean Whincup and Owen’s co-driver Chaz Mostert will start on the front row of the grid for Saturday’s final qualifying race beginning at 4.15pm AEST.

But the action rook place behind them, with Winterbottom’s co-driver Dean Canto served a drive-through penalty for making contact with Lowndes’ co-driver Steve Richards in car No.888.

Canto burst from 11th on the grid and weaved his way to a strong position but bashed Richards’ Commodore from behind, turning him around around into the first corner.

The shunt also drew in Tony D’Alberto, who was sent off the track.

All three cars ended up at the back of the pack, with Richards recovering to be 18th, D’Alberto finishing 21st and Canto ending up second-last in 25th.

D’Alberto’s co-driver Scott Pye was scathing on his fellow Ford man Canto for his “stupid” approach.

“He’d already made up a few places, I mean how many do you want before the first corner,” he said.

Pye absolved D’Alberto of fault, saying “we couldn’t have asked for any more from him”.

Erebue Motorsport’s Chris van der Drift only completed half of the 20 lap race after an off-road trip blew out a tyre.