The opening salvo of the Intercontinental GT Challenge round was headed by polesitter Maro Engel's GruppeM Mercedes ahead of the similar Triple Eight machine started by Maxi Gotz, the Manthey Porsche with Thomas Preining at the wheel, Luca Stolz in the SunEnergy1 Mercedes and Augusto Farfus's WRT BMW M4.
Audi's best hope of victory was eliminated from contention just half an hour into the race when Christopher Haase was punted into the Turn 2 wall by Duvashen Padayache’s Valmont Racing Mercedes.
The order of the lead bunch was unchanged in a tight opening stint as Engel edged away from Gotz, while Dries Vanthoor in the second WRT BMW moved through the lower reaches of the top 10 to claim sixth.
Two-time Bathurst 1000 winner Chaz Mostert fell foul of the pitlane exit line as he emerged for his first stint aboard the #65 Pro-Am Audi on cold tyres and earned himself a drive-through penalty.
SunEnergy1, the defending event winner, jumped team owner Kenny Habul ahead of the Porsche now with Mathieu Jaminet inserted, but the French factory ace soon overcame the 49-year-old gentleman driver on lap 40. Habul then dropped behind Maxime Martin (in for Farfus) and the leading Pro-Am entry of Audi driver Frederic Vervisch - the Belgian also passing his compatriot - before Charles Weerts (in for Vanthoor) demoted Habul to seventh.
Mostert recovered strongly after dropping a lap down with his penalty, and soon unlapped himself from leading pair Mikael Grenier (in for Engel) and Gotz.
Shortly after Vervisch pitted from fourth to hand over to Brad Schumacher, the first caution of the race followed when Stephen Grove shunted his Porsche at Skyline.
Leader Grenier pitted one lap later than the rest of the lead bunch and so dropped to sixth for the restart, with van Gisbergen installed in the lead car ahead of Jaminet and MotoGP legend Valentino Rossi (in for Martin). Weerts was elevated to fourth ahead of Habul, who soon dropped behind Grenier upon the resumption of hostilities.
Mostert handed the MPC Audi back to Liam Talbot to get the amateur’s drive-time nearer completion and he came out in seventh, although that became sixth when Habul had a brief off before serving a penalty for a pit exit violation. He came in again on the following tour to hand over to Jules Gounon.
At the quarter distance, van Gisbergen and Campbell had pulled clear of the chasing WRTs, Weerts unable to shake the pursuing Grenier.
After three hours, the Valmont Racing Mercedes led the Silver-rated category, between the second and third Pro-Am cars of Christopher Mies (The Bend Audi) and Jamie Whincup (Boost Mobile Racing Mercedes).