Ford driver Mark Winterbottom has lit the fuse for a lively finish to the V8 Supercar season this weekend by questioning Holden's commitment to teamwork.
After sealing the drivers' championship at Winton two weeks ago, Jamie Whincup said earlier this week he'll be doing "whatever it takes" in Sydney to ensure his Holden teammate Craig Lowndes climbs above Winterbottom to claim second spot.
A Holden one-two would replicate last season's effort and be a perfect way for the team to sign off on a 20-year head-to-head rivalry with Ford before Nissan and Mercedes join the category in 2013.
Winterbottom doubts whether Whincup will follow through with his promise to help his teammate given the 29-year-old Holden star's failure to win at Sydney Olympic Park over the three-year history of the race.
"Jamie has won the championship but he's never had a good result here so he's got his own personal reasons why he'd want to win the weekend," said Winterbottom, whose best title result was a runner-up finish to Whincup in 2008.
"He'd want to beat Lowndes anyway."
"I'm sure as soon as you put your helmet on, as much as you say you're going to help your teammate, the competitive streak sets in and it always changes."
Winterbottom, who holds a narrow 63-point lead over Lowndes with 300 points up for grabs over the weekend, is upbeat about his prospects for the two 250km races after winning the Sunday race last year.
"I wanted to come here fighting for the championship but now that's gone I've got to try to wrap up second," he said.
"I knew they'd be trying to do it (team up) but my plan is to get out in front and not even worry about those two."
Whincup sped to the title in spectacular style in Victoria, showing all his skill and courage to move from 23rd after a pit-lane penalty to finish third and bank enough points for an unassailable lead.
While Whincup has been the standout driver over the past five seasons, the four-time champion's best result at the tight Homebush street circuit is fifth.
The track remains the only one on the current schedule where Whincup has never won a race.
The Triple Eight team pilot believes that although he hasn't prepared as well as he could've in previous years, his races have been cruelled by mechanical problems.
"I've been in the box seat before. I've led the race three times and it's turned pear-shaped," said Whincup.
"We've had steering and gear box issues at crucial times.
"We've been very quick here but it just hasn't gone our way."
Temperatures of up to 36C have been forecast for Saturday with possible thunderstorms on Sunday.