Chaz: I'm not holding back

Chaz Mostert emphasised he would not hold back from racing teammate Mark Winterbottom, as it becomes more and more likely the two will be locked in battle for this year's V8 Supercars Championship.

While Mostert left the year's first event 22nd in the points, he's tried to eliminate errors and has been a powerhouse performer recently, roping in the ARMOR ALL Pole Positions and racing hard at the front.

In Sunday's Wilson Security Sandown 500 he was threatening, and paired with speedy young gun Cameron Waters, finished just 0.65 seconds off the leader.

The leader happened to be Winterbottom, who extended his points lead over Mostert by 24 after a sneaky pass on the #6 Falcon, while Mostert was focussed on grabbing Shane van Gisbergen.

While he acknowledged how difficult it is to race a teammate out front, Mostert told v8supercars.com.au he wouldn't have shied away from making the pass on Winterbottom if he had been close enough.

As the reigning Supercheap Auto Bathurst 1000 champ, don't expect him to hesitate next event, either.

"To be honest I was trying my hardest out there - I'm not holding back or anything like that, which people constantly think," the Pepsi Max driver said.

"I don't really like punting someone off to take the win off them and definitely it's not good to do that to your teammate. So I tried my hardest."

Mostert believes that since he and Winterbottom both race a similar car, it can be harder to pass one another than other competitors on track. He emphasised in the post-race press conference how quick Frosty's car was at Sandown too, while revealing he was struggling with the #6 for much of the day.

"The hardest thing, that people don't understand, is you're racing a car that has the same strengths as you and very similar weaknesses," Mostert said.

"So it's very hard ... what your car is, is what you [have to] do it with.

"But we worked hard and it was good to get in that last sector and really just try and rattle him a little bit, maybe have a little bit of a look.

"I just wasn't close enough and what really hurt us was those couple of stints not having turn and where Frosty got the track position back on top."

There had been contact between the two Pepsi Max Falcons on Saturday during the primary driver qualifying race, but Mostert shrugged it off at the time saying Winterbottom couldn't see him in the glare.

Prodrive team boss Tim Edwards has continued to say the pair is free to race, and believes that regardless of Championship position they won't "do anything silly".

"They both know that the last thing you want to do is take your teammate out," Edwards said.

"When Mark's behind he's going to put the pressure on, when Chaz is behind he's going to put the pressure on but neither of them are going to make a big lunge on the other because the last thing you want to do is take your teammate out.

"They're both mindful of where they are in the championship and will race each other as hard as they can but they're never going to do anything silly like that."

While Edwards told v8supercars.com.au Mostert's fuel load was a lot tighter than Winterbottom's during the 500km race, Mostert explained he was having trouble with the car and it took until the final stint to be where he wanted it.

"We struggled with the car a lot - I think we had a little bit of damage from some of the early stints. It could've been me, I'm not too sure, but we just had massive understeer," he said.

"We tuned it up, every time we came in we put more we changed the car to make it turn more. The car got better and better the last stint it was probably the closest it was to qualifying, so it was good."

After Sunday's race Prodrive stablemate David Reynolds has moved to third in the Championship, making it a battle of three FG X Falcons - the gap from Reynolds to Winterbottom is 360 points. Craig Lowndes is now 423 points away with Red Bull teammate Jamie Whincup languishing in eighth. Whincup's lowest championship finish in recent times was 10th in 2006, his first year with Triple Eight.