Chaz Mostert and Will Brown largely kept quiet on Friday in Perth
Mostert 17th, 21st in two practice sessions, Brown 18th and seventh
Both drivers positive performance will be found in Saturday qualifying
The last two Repco Supercars Champions, Chaz Mostert and Will Brown, find themselves with work to do to entrench themselves into the battle at the top end of town at the Bosch Power Tools Perth Super 440.
Reigning champion Mostert particularly struggled to dial in his #1 Toyota Supra in its first encounter with Motormall Wanneroo Raceway, finishing the day's back-to-back practice sessions in 17th and 21st.
Teammate Ryan Wood was 21st and 20th in the two sessions, and ended the day with contact with Kai Allen in the final minutes of Practice 2.
Mostert has insisted that Walkinshaw TWG Racing can get themselves back into contention, with the compressed nature of Friday's running impacting on how closely the teammates could feed off one another.
"It was absolutely chaotic out there, two 25 minute sessions with a five minute break, it felt like that in the middle," said Mostert post-session.
"We didn't roll out too strong on our side of the garage, I'm not sure where Woody ended up. When you have those two practice sessions you have no time to work together.
"Not where we want to be, but we'll go back to the drawing board tonight and have a bit of a look. No doubt we know how to make fast cars around here, so we'll see if we can tune it up overnight.
"It's pretty tricky, probably a bit of turn for me, I really struggled for getting the rotation at Turn 1, 4, 6. [Turn] 7 I wasn't too bad, something about them long, sweeping corners, my car is not quite in the window.
"Sam [Scaffidi, engineer] has got a few ideas of where we're at and we'll see if we can tune it up."
Brown meanwhile declared that Friday was one of his "tougher" practice sessions of the year, despite ending the day seventh fastest.
That came after Brown was a lowly 18th in Practice 1, whilst Broc Feeney rediscovered speed on the other side of the Red Bull Ampol Racing Garage to end the day second, though over two tenths behind the blistering speed of Matt Payne.
Entering the weekend seventh in points off the back of a solid run since returning from the New Zealand Double Header, Brown was happy with performance gains found throughout the second session, but knows more can be found.
"I'm not sure to be honest, I think that was one of our tougher sessions this year. At Townsville we were P2 and felt quite good in Practice and then dropped back," said Brown after jumping out of the #888 Ford.
"Then, probably struggled at the start. We thought it might've been tyres, and then we put another set on.
"It's tight between second and that, but Payne's up the road again, so looks like that's obviously the car to beat again this weekend, but we've still got a fair bit of work to do.
"We changed a lot then, I actually felt like we made a lot of good gains from the start of the session, I wasn't happy with how we rolled out.
"I think we got a lot better towards the end then, the new tyres helped. I think I could've done a little bit better job on the greens, just with tidying up a few things, but I'm sure that's every car out there.
"Everyone's gonna work at it overnight and it all tightens up, so we're gonna try and do the best job tonight that we can and find a couple of tenths in this thing."
Saturday Supercars action begins with back-to-back Boost Mobile Qualifying sessions from 9:45am local time/11:45am AEST.
