Scott McLaughlin beat Chaz Mostert to win the opening leg of the Truck Assist Winton SuperSprint, despite a first-lap clash with team-mate Fabian Coulthard.
The Shell V-Power Racing Mustangs made contact on the opening lap, Coulthard penalised for the Turn 5 incident and ultimately finishing 15th.
McLaughlin rejoined in third, and took the lead after the pitstops, when David Reynolds served a penalty of his own.
He had Mostert for close company on the way home, but did enough to keep the Supercheap Auto Mustang at bay and win by 1.3013 seconds.
"It’s an awkward one. I didn’t know if Fabian was 100 percent there, I thought it was my corner, I was in front far enough," McLaughlin said of the clash.
"I went off the road and tried to get back and rejoin in the right position, but I was going to go the wrong way, so I was dammed if I did and dammed if I didn’t.
"I pushed on and thankfully it was OK."
Reynolds rounded out the podium ahead of James Courtney, who he bumped out of the lead on lap two to incur a penalty.
Coulthard withstood a stern challenge from polesitter Mostert into Turn 1 to take the lead, but was passed by Courtney after making a mistake exiting Turn 3.
McLaughlin leapt from fifth to third, only for a look around the outside of Coulthard at Turn 5 to result in contact between the Shell Fords.
While Coulthard fell to 23rd, McLaughlin took the shortcut to the exit of Turn 8 and slotted back into third.
Stewards ultimately handed Coulthard a 15-second time penalty for the contact, and took no further action on McLaughlin's rejoin.
Courtney only led until a touch from Reynolds at Turn 4 on lap two, which dropped the Mobil 1 MEGA Racing Commodore to fourth.
That all left Reynolds leading McLaughlin and Mostert through the first stint, but the Penrite Holden was handed a five-second penalty for the contact with Courtney.
McLaughlin was the first of the group to pit, on lap 12 of the 40, staying ahead of Mostert, who stopped seven later.
With Reynolds' penalty, that became the fight for the lead, Mostert right behind McLaughlin entering the final 15 laps.
Mostert could not challenge McLaughlin, though, who claimed a ninth victory in his title defence, matching his 2018 haul.
With the results, McLaughlin extends his championship lead over Coulthard to 232 points after 13 races.
Second for Mostert is the Tickford Racing driver's fifth podium of the campaign.
"At the start, Fabs got a bit of a nose on me and he came to mid-track, but when you’re off pole you’re not going to back out," Mostert said.
"A bit like Ayrton Senna was, when there’s a gap you’re going to go for it, I had a crack, there was a bit of argy-bargy, but we got it back and finished second."
Of McLaughlin's rejoin right ahead, Mostert said: "I’ll cry about it just to try and get first, but at the end of the day he got hit off, so it wasn’t his fault that he went off.
"It’s the toughest thing here, and with the rain it’s very slippery, so it’s hard to get back [to the track], but at the end of the day he was the fastest guy so I feel like he deserved the win."
Reynolds pitted on lap 20 from the lead, but his penalty meant he rejoined fourth, also behind the early-stopping Jamie Whincup.
He cleared the Red Bull Holden, but then had to withstand pressure from Courtney – on fresher tyres – on the run home.
That was how the Commodores stayed, third a second podium of the year for Reynolds and fourth a season-best for Courtney.
Shane van Gisbergen and Nick Percat pitted last of all after starting 12th and 17th, and rejoined sixth and ninth on lap 28.
Van Gisbergen reeled in team-mate Whincup to take fifth place with four laps remaining, while Percat crossed the line seventh.
From 10th on the grid, Whincup was the first driver to pit, on lap five, putting an undercut to good use through the first half of the race.
Lee Holdsworth crossed the line eighth, but fell to 16th with a 15-second time penalty for a clash with Anton De Pasquale, who finished 19th.
That handed Andre Heimgartner, Mark Winterbottom and Scott Pye the final places in the top 10, Heimgartner having started 20th in his Nissan.
Garry Jacobson ran in the top 10 early after qualifying a career-best eighth, but he eventually finished 22nd following a spin in the first stint.
Simona De Silvestro, Jack Smith and Richie Stanaway rounded out the order, having been involved in a final-corner incident on lap two, for which Stanaway was penalised.