Rick Kelly has boosted Nissan's hopes of more Top End success by recording the quickest lap during the opening Supercars practice session in Darwin.
Kelly's lap of 1min 6.5061sec topped the timesheets at Hidden Valley Raceway on Friday, with Holden's big guns on his tail.
Teammate Michael Caruso broke the manufacturer's three-year winning drought at last year's event.
Triple Eight Racing's Craig Lowndes was second-fastest in practice, while Red Bull Racing teammates Shane Van Gisbergen and Jamie Whincup were third and fourth respectively.
Ford's Chaz Mostert rounded out the top five.
Despite posting the quickest time, Kelly said it wasn't the cleanest of laps.
"We ran a new set of tyres and I don't think anyone else did," Kelly said.
"We've only done a couple of runs here to race on. There's certainly more to come.
"The guys have done a really strong amount of work in the last four weeks so there's lots of new stuff on the car we're trying.
"It seems to have really paid off."
With a little less than five minutes remaining, Holden veteran Jason Bright spun into a tyre embankment, damaging the rear of his car and causing the session to be put on hold.
The fastest times were posted after the resumption but championship leader Fabian Coulthard (seventh) and DJR Team Penske teammate Scott McLaughlin (14th) couldn't elevate themselves into the top bracket.
Friday's second practice session is due to start at 1500 local time (1530 AEST).