V8 Supercar Championship Series leader Jamie Whincup restored order at the Queensland House and Land.com 300 on Saturday with victory over Jim Beam Racing's James Courtney and Ford Performance Racing's Mark Winterbottom.

But he admitted it could have been a different story had his and the team's mentality not changed from the last event in Melbourne at the Norton 360 Sandown Challenge.

“Sandown was just a poor result from everybody across the board,” Whincup explained. “We were thinking about next year [when we will defect to Holden] and getting way too far ahead of ourselves with everything that was going on.”

Whincup was disappointed though with the way he extended his Championship lead over closest challengers Will Davison and Garth Tander, who both failed to finish today's race.

“That's not racing,” Whincup said. “It's really unfortunate that my biggest rivals got knocked out today. We need to get out there racing and settle this thing on the track, that's how it should be.”

Davison has dropped 267 points behind with the result: “After qualifying we sacrificed the race running on hard tyres and a mid-field result would have been tough enough, let alone a DNF,” Davison said.

“At this stage of the Championship you really can't afford to do that, so a DNF is devastating. On a positive note, we have fresh soft tyres for tomorrow, not many others do, so we'll try claw back as many points back as we can.”

Whincup would still not let up coming into the unpredictable endurance events of the L&H 500 at Phillip Island and the Supercheap Auto Bathurst 1000.

“You still keep racing (despite a lead) and pushing hard. That whole lead can turn into a deficit in one day at Bathurst.”

Both TeamVodafone cars suffered oil leaks, the worst of which forcing Craig Lowndes to also retire. Whincup admitted it was a great concern with one race remaining tomorrow.