In a session which set the top and bottom 50 percent for qualifying later in the day, Waters clocked a 2:02.9190s just before the chequered flag to put the #222 Mercedes-AMG on top by a margin of 0.0256s over the #888 Mercedes-AMG.

Jordan Love made it Triple Eight Race Engineering entries second and third, ahead of the #27 Heart of Racing/SPS Mercdes-AMG and the #22 Melbourne Performance Centre Audi, with the #911 Manthey EMA Porsche sixth.

With the 30-car field to be split in two for qualifying, the top 15 was the first aim for all of the GT3 entries.

The session was extended from 60 to 65 minutes because, after an opening lap circuit safari, there was an early Full Course Yellow procedure test.

Thomas Randle had managed to squeeze in a 2:07.6535s in between in the #222 STM Mercedes-AMG, before the circuit went green again with a touch over 55 minutes remaining.

Glen Wood moved the marker to a 2:07.5961s in the #48 M-Motorsport Mercedes-AMG in the first flyers after the FCY, before Alessio Picariello and Matt Campbell made it a Manthey EMA Porsche one-two on a 2:04.7480s in the older Pro-Am entry and a 2:05.1360s in the newer Pro car respectively.

Campbell improved to a 2:04.9254s two laps later in the #912 Porsche, after which Triple Eight’s Mikael Grenier set a 2:04.8488s in the #888 Mercedes-AMG.

The pace continued to pick up when Joel Eriksson (#13 Phantom Global Racing Porsche) set a 2:04.5823s, Grenier a 2:04.2151s, and Campbell a 2:04.1102s in quick succession.

Campbell laid down a 2:03.7166s next time through but that was knocked off when Jules Gounon clocked a 2:03.6691s in the #75 SunEnergy1 Mercedes-AMG.

A red flag came in the 28th minute when Adam Hargraves crashed the #20 T2 Racing IRC on the run into McPhillamy Park, bringing about a halt to proceedings of around 12 minutes.

The lost track time also meant lost time to burn off fuel loads in readiness for the final flings, and the push was on when the session resumed with 40 minutes left.

Waters shifted the benchmark to a 2:03.5687s in the #222 STM Mercedes-AMG before he was pipped by Kelvin van der Linde’s 2:03.4465s in the #22 MPC Audi with just under a quarter of an hour remaining.

Lee Holdsworth then hauled the Pro-Am class #9 MPC Audi, which he is sharing with Dean Fiore and Marc Cini, to second on the timing monitor on a 2:03.5248s.

As the session moved into its final 10 minutes, Love reset the fastest lap with a 2:03.0965s in the #88 Mercedes-AMG and Ross Gunn took up second on a 2:03.2560s in the #27 Heart of Racing/SPS Mercedes-AMG.

Love was then usurped by Triple Eight team-mate Feeney, who wheeled the #888 Mercedes-AMG to the first ‘two’ of the day, a 2:02.9446s with four minutes left.

Waters, however, would have the last laugh, and then a crash for the Invitational class KTM X-Bow effectively put paid to the session by triggering a yellow flag at Forrest’s Elbow as drivers completed their final laps.

Replays showed Trent Harrison hitting the wall on approach in the #50 KTM Vantage Racing entry, leaving the team with work to do in order to fix the damage.

The top 10 was thus the #222 Mercedes-AMG, the #888 Mercedes-AMG, the #88 Mercedes-AMG, the #27 Mercedes-AMG, the #22 Audi, the #911 Porsche, the #9 MPC Audi, the #46 Team WRT BMW, the #75 SunEnergy1 Mercedes-AMG, and the #32 WRT BMW.

Also through to the quicker half of qualifying was the #912 Manthey EMA Porsche, the #130 GruppeM Racing Mercedes-AMG, the #77 Craft-Bamboo Racing Mercedes-AMG, the #44 Valmont Racing/Tigani Motorsport Audi, and the #2 MPC Audi.

Qualifying starts at 12:40 local time/AEDT/UTC +11, with Part 1 for the bottom 50 percent and Part 2 from 13:30 for the top 50 percent, followed by the top 10 ‘shootout’ later in the afternoon.

Results: Practice 6 All drivers