Kostecki, who broke through for his maiden Supercars win on Friday, took the flag ahead of Shane van Gisbergen but may face sanction after the Erebus Camaro appeared to baulk Declan Fraser upon its release from the pits.
At the very front it was a mostly straightforward start to the race as Kostecki charged into the lead from pole, followed by his team-mate Will Brown and Bryce Fullwood's BJR Camaro.
But there was plenty of drama right behind the lead group, starting with Team 18 driver Mark Winterbottom smacking the Turn 5 fence while scrapping over fifth place with James Golding.
The same corner claimed another victim a lap later when Macauley Jones and Matt Payne made contact that sent Jones into the back of Anton De Pasquale.
The Dick Johnson Racing Ford then speared into the wall and was out of the race, with Payne later handed a drive-through penalty for instigating the shunt.
At the same time James Courtney pulled into pitlane with his Tickford Mustang suffering a significant engine fire similar to that seen in Nick Percat's WAU car yesterday. The veteran managed to get the car into the lane so that fire crews could intervene and then extricate himself safely.
The race went green again on lap six with a time certain finish in place for lap 11.
The immediate opening of the pit window meant Tickford's Cam Waters, the only driver left in the field on hard tyres thanks to De Pasquale's issue, dived into the pits from the back of the field to take the super softs.
The super soft starters then started to hit the lane on lap nine for hards, the second-place team cars first to make their stops. That was bad news for Brown who pitted from second, but was always going to lose several spots while others circulated for an extra lap on their softer rubber.
Brown duly slipped back to fifth after the leaders pitted on lap 10, with Kostecki retaining his lead from Will Davison, Fullwood and van Gisbergen.
But the manic round of lap 10 stops soon played into Brown's hands, with both Davison and Fullwood penalised for unsafe releases.
For Fullwood the issue was contact with Fraser on his release, while Davison clobbered into one of van Gisbergen's tyres as he left his box and sent it flying.
Their respective 15-second penalties dropped them to 11th (Davison) and 12th (Fullwood) in the final standings.
Kostecki went on to win the race, however he too wasn't spared a post-race investigation of his own. As it stands, van Gisbergen is second while Brown was elevated back to third by the penalties for Davison and Fullwood.
Chaz Mostert ended up fourth after surviving a mid-race tussle with Andre Heimgartner and Golding that left the latter in a spin.
Heimgartner came home fifth ahead of Jack Le Brocq, Broc Feeney, Tim Slade, Thomas Randle and Waters, who made decent headway with his off-kilter strategy.
The Melbourne SuperSprint concludes with a final sprint race at 10:25am tomorrow.
Supercars Albert Park Race 3 Classification (11 laps)
| Cla | Driver | Car | Time | Gap |
|---|---|---|---|---|
| 1 | Brodie Kostecki | Chevrolet | 26'25.0187 | |
| 2 |  Shane van Gisbergen |
Chevrolet | 26'27.4591 | 2.4404 |
| 3 |  Will Brown |
Chevrolet | 26'31.0172 | 5.9985 |
| 4 | Chaz Mostert |
Ford Mustang GT | 26'31.4599 | 6.4412 |
| 5 | Andre Heimgartner |
Chevrolet | 26'34.9733 | 9.9546 |
| 6 | Jack Le Brocq |
Chevrolet | 26'35.5715 | 10.5528 |
| 7 | Broc Feeney | Chevrolet | 26'36.1832 | 11.1645 |
| 8 | Tim Slade |
Chevrolet | 26'37.5480 | 12.5293 |
| 9 | Thomas Randle |
Ford Mustang GT | 26'39.2492 | 14.2305 |
| 10 | Cameron Waters |
Ford Mustang GT | 26'39.4014 | 14.3827 |
| 11 | Will Davison |
Ford Mustang GT | 26'41.0800 | 16.0613 |
| 12 | Bryce Fullwood |
Chevrolet | 26'41.4048 | 16.3861 |
| 13 | Declan Fraser | Ford Mustang GT | 26'42.4493 | 17.4306 |
| 14 | David Reynolds |
Ford Mustang GT | 26'44.1392 | 19.1205 |
| 15 | Todd Hazelwood |
Ford Mustang GT | 26'45.4621 | 20.4434 |
| 16 | Nick Percat |
Ford Mustang GT | 26'46.0618 | 21.0431 |
| 17 | Cameron Hill | Chevrolet | 26'46.2317 | 21.2130 |
| 18 | Jack Smith |
Chevrolet | 26'49.3886 | 24.3699 |
| 19 | James Golding |
Chevrolet | 26'49.5524 | 24.5337 |
| 20 | Scott Pye |
Chevrolet | 26'56.2715 | 31.2528 |
| 21 | Matthew Payne | Ford Mustang GT | 27'18.4296 | 53.4109 |
| Anton De Pasquale |
Ford Mustang GT | 1'58.2125 | 10 Laps | |
| Macauley Jones |
Chevrolet | 1'59.6823 | 10 Laps | |
| James Courtney |
Ford Mustang GT | |||
| Mark Winterbottom |
Chevrolet | |||
| View full results | ||||
