Perth SuperNight Supercars: Scott McLaughlin wins for DJR Penske Ford

Despite falling behind Whincup for the first stint, an undercut around the first stops set up a 1.9-second win for the reigning series champion.

Whincup was forced to settle for second, as Cam Waters held off Fabian Coulthard to take the final spot on the podium.

For the second night in a row McLaughlin made a sluggish getaway from pole, which allowed Whincup to sweep into the lead at Turn 1.

The pair then staged a 17-lap battle for the lead, with Whincup narrowly holding on out front before McLaughlin dived in for his first stop.

On lap 25 of 83 the leader pitted and Whincup's Triple Eight Holden took on more fuel than McLaughlin.

That meant Whincup rejoined behind the #17 DJR Penske Ford, but crucially just ahead of McLaughlin's team-mate Coulthard - winner of the previous two races.

As the first stops shook out McLaughlin's lead hung around the 6s mark, with Coulthard running third.

Coulthard kicked off the second round of stops on lap 47, just moments before a clash with Andre Heimgartner left Scott Pye stranded at Turn 7.

That led to the safety car being called three laps later, which meant Coulthard dropped to fourth behind Waters as the other leaders stopped under the caution.

After the restart McLaughlin quickly built a 1.2s lap over Whincup, who had mirrors full of Waters and Coulthard.

That was all the break that McLaughlin needed, the gap ballooning out to around 2.5s before slimming back to 1.9s as he controlled the closing laps.

The battle for second took slightly longer to resolve itself, although Whincup did manage to pull away from Waters and Coulthard as the final stint wore on.

The two Mustangs scrapped over third for even longer, Waters ultimately getting home ahead of the Penske Ford.

Shane van Gisbergen finished fifth despite a scrape with Rick Kelly, followed by Erebus pair David Reynolds and Anton De Pasquale.

Will Davison finished eighth, while Lee Holdsworth was a fine ninth after starting all the way down in 20th.

The only Mustang to miss the top 10 was Chaz Mostert. Having run third in the early stages, sitting around 1.5s behind the leaders, the Tickford driver started to slip back at around the 20-lap mark.

The culprit was an engine problem, which first caused a lengthy stint in the garage before Tickford retired the car from the race.

McLaughlin's eighth win from this year's 12 races means he leads Coulthard by 142 points in the standings, while van Gisbergen is over a round's worth of points behind in third.

Race two result

Drivers' standings