Lowndes finished 12th in both races but kept hold of his title lead.
Red Bull Racing Australia teammate Jamie Whincup made up some ground, his ninth and sixth placings shooting him up from fifth to third on the overall standings.
It was a horror afternoon, however, for Holden Racing Team, whose two lead drivers James Courtney and Garth Tander collided on the opening lap of race two.
Courtney, in his 300th start in V8 Supercars, lunged into Tander and sent them both off-track, collecting innocent passers-by Lee Holdsworth and James Moffat.
Courtney began the day in second on the drivers' standings, but ended it fourth. Volvo's Scott McLaughlin, who started and finished last in race one, bounced back with ninth place in race two.
Fellow Kiwi Shane Van Gisbergen was eighth and fifth and sits sixth on the overall standings, one place behind Fabian Coulthard, who was sixth and 21st yesterday.
The round will wrap up with a 67-lap race this afternoon.
- AAP