Shane van Gisbergen made it two wins from two V8 Supercars races at Eastern Creek, as a fresh assault of rain between races one and two made conditions treacherous again.
The leaders were four abreast into Turn 1, with van Gisbergen taking the honours and leading out of the corner, beating poleman Scott McLaughlin, Jamie Whincup and Fabian Coulthard.
McLaughlin's Garry Rogers Motorsport engineers had worked tirelessly between races to change his engine following the race one retirement, but the Volvo would lose a wheel early in the race, falling nine laps down as a result.
That incident allowed Whincup to move into second, and while he looked to have some pace to challenge van Gisbergen, Robert Dahlgren's off at Turn 5 in the other Volvo brought out the safety car and prevented Whincup from progressing towards the lead.
On the restart Coulthard and James Moffat edged Whincup out wide for second and third, but Moffat soon drifted wide himself and fell right back to 17th.
Van Gisbergen also showed he was mortal, going wide into the grass, and although he was able to maintain the lead, his advantage was right back down to less than a second.
Coulthard then fell down the order to fifth as he struggled for grip, while van Gisbergen managed to pull away from Whincup in second, helped by the championship leader running wide and falling seven seconds behind.
That allowed Chaz Mostert to catch the tail of Whincup, before another safety car as a result of Scott Pye's retirement set up a dramatic dash to the finish.
When the green flag was waved van Gisbergen and Whincup went side by side, but it was Mostert who took the advantage by passing Whincup, and he almost got the jump on van Gisbergen.
Given one more lap Mostert might have overtaken the race one winner, but it was van Gisbergen who held off the Ford Performance Racing driver for the win, with Whincup third.
Jason Bright drove a measured race to bring his Brad Jones Holden home fourth, and Will Davison kept it clean to finish fifth.
Results - 24 laps: Pos Driver Team/Car Time/Gap 1. Shane van Gisbergen Tekno Holden 47m02.9787s 2. Chaz Mostert FPR Ford +0.7167s 3. Jamie Whincup Triple Eight Holden +3.3736s 4. Jason Bright Brad Jones Holden +5.4642s 5. Will Davison Erebus Mercedes +8.8532s 6. James Moffat Nissan +11.2052s 7. Fabian Coulthard Brad Jones Holden +14.3714s 8. James Courtney HRT Holden +15.1094s 9. Rick Kelly Nissan +16.0602s 10. Russell Ingall Dumbrell Holden +16.9037s 11. Craig Lowndes Triple Eight Holden +17.3905s 12. Mark Winterbottom FPR Ford +19.1792s 13. David Reynolds Rod Nash/FPR Ford +20.4292s 14. David Wall Dick Johnson Ford +24.7174s 15. Lee Holdsworth Erebus Mercedes +26.8372s 16. Jack Perkins Schwerkolt/FPR Ford +29.5075s 17. Todd Kelly Nissan +29.6956s 18. Dale Wood Britek/BJR Holden +33.6576s 19. Nick Percat Walkinshaw/HRT Holden +34.3539s 20. Michael Caruso Nissan -1 lap 21. Scott Pye Dick Johnson Ford -2 laps Retirements: Garth Tander HRT Holden 21 laps Scott McLaughlin GRM Volvo 8 laps Robert Dahlgren GRM Volvo 1 lap Tim Slade Rosenberg/HRT Holden 0 laps