Erebus Motorsport Mercs have recorded the day's fastest times in the closing minutes of Friday practice in Townsville.
The Mercedes Benz AMG E63s were separated by just 0.864 seconds, with Lee Holdsworth just toppling teammate Will Davison with a 1min13.7919.
Holdsworth recorded the team's first win in the Erebus guise earlier this season at Winton; while Davison won at the Townsville circuit on Saturday last year, though in a Ford Performance Racing Falcon.
The top four cars were all within one tenth of a second, Volvo's Scott McLaughlin and Holden's Jamie Whincup right on the tail of the Erebus machines.
Earlier fast man Shane van Gisbergen finished fifth, with Jason Bright, Nick Percat, James Courtney, Garth Tander and Mark Winterbottom completing the top 10.
Others to note include Fabian Coulthard 11, first Nissan Rick Kelly 12, Craig Lowndes 14 and Chaz Mostert 17.