Supercars championship leader Scott McLaughlin has qualified his Ford Mustang fastest for Saturday’s co-driver sprint race at the Sandown 500.

The DJR Team Penske star completed a one minute and 07.7736 second fastest lap in the 20-minute qualifying run to pip Holden’s Jamie Whincup (1:07.9159) to top spot.

It means McLaughlin’s co-driver Alex Premat will start the 60km race at the front of the grid alongside Whincup’s partner Craig Lowndes.

Nissan’s Andre Heimgartner qualified third (1:07.9398) ahead of Shane Van Gisbergen (1:07.9663), putting Bryce Fullwood and Garth Tander on to the second row.

Another Nissan driver, Garry Jacobson qualified fifth to put co-driver Dean Fiore into the mix for a strong result.

McLaughlin, driving a newly built Mustang after a car-wrecking crash on the Gold Coast last month, is aiming to wrap up this year’s championship this weekend.

He made the most of a drying track after rain lashed the 3.1km circuit at the start of the session to lay down his impressive time.

“I was just watching the track dry those first three laps I was out there and I was trying to look after the tyre and then the boys said ‘they’re going a bit faster’ … I knew that the track grip was there so had a go and it was really good,” McLaughlin told Fox Sports.

“Once I got it hooked up and got going round the back where it was a bit drier, (it) was good.”

The first of two 60km races on Saturday will be limited to co-drivers only.

How they finish will then determine the grid for a second 60km race, which will feature the full-time drivers and give McLaughlin a chance to extend his whopping 463-point championship lead.

Saturday’s second race will also determine the starting grid for Sunday’s 161-lap, 500km endurance race.

The co-driver race begins at 2.25pm.