Gordon Shedden gave the Honda Civic Tourer its first British Touring Car Championship victory with a last corner effort in the Donington Park finale.
Shedden was only sixth in the early stages, while Colin Turkington's WSR BMW led comfortably from pole, even after a safety car period.
But after a superb fight with team-mate Matt Neal and the Motorbase Ford Focus of Mat Jackson, Shedden closed on the second-placed MG6 of Jason Plato.
The MGs started to struggle on the soft Dunlop tyre that all the runners were on for race three and Shedden dived by Plato into the chicane around two-thirds distance.
At that stage, Turkington's lead was five seconds and victory looked certain. But the BMW's tyres started to go off and Shedden closed in.
He arrived on the leader's tail on the final lap. Shedden attacked around the outside at McLeans, only to get run out into the gravel by Turkington.
The Honda challenged again on the outside into the final chicane. Turkington defended again and contact was made.
Both cars ran across the gravel, but Shedden got out first to cross the line and take his first win of the season.
With Plato falling back to an eventual sixth, the podium was completed by Neal's Honda.
Jackson gave Motorbase some cause for optimism, in a race in which Fabrizio Giovanardi was involved in an incident behind the safety car and got track limits warnings, with fourth.
Reigning champion Andrew Jordan fell down the field with a sideways moment at the first corner, but recovered brilliantly to finish fifth. He is now tied for the points lead with Plato.
Rob Collard finished his impressive day by claiming seventh after starting from the back, with team-mate Nick Foster making it three BMWs in the top eight.
Just as at Brands Hatch, Alain Menu's BMR VW Passat was impressive on the soft rubber and came through from last on the grid to finish ninth.
Race two winner Sam Tordoff fell to 16th, just behind Giovanardi.
Results - 18 laps: Pos Driver Team/Car Time/Gap 1. Gordon Shedden Honda 23m22.396s 2. Colin Turkington WSR BMW +0.502s 3. Matt Neal Honda +3.937s 4. Mat Jackson Motorbase Ford +6.365s 5. Andrew Jordan Eurotech Honda +9.777s 6. Jason Plato MG +13.587s 7. Rob Collard WSR BMW +16.680s 8. Nick Foster WSR BMW +18.090s 9. Alain Menu BMR VW +19.196s 10. Adam Morgan Ciceley Mercedes +19.582s 11. Aron Smith BMR VW +19.912s 12. Jack Goff BMR Vauxhall +20.023s 13. Tom Ingram Speedworks Toyota +22.399s 14. Lea Wood Houseman Toyota +25.451s 15. Fabrizio Giovanardi Motorbase Ford +26.516s 16. Sam Tordoff MG +28.711s 17. Jack Clarke Motorbase Ford +29.509s 18. Martin Depper Eurotech Honda +31.345s 19. Dave Newsham AmD Ford +38.286s 20. Simon Belcher Handy Toyota +39.797s 21. Chris Stockton BTC Chevrolet +42.386s 22. Aiden Moffat Moffat Chevrolet +43.689s 23. Daniel Welch Welch Proton +46.431s 24. Ollie Jackson Welch Proton +1 lap 25. Hunter Abbott RAR Audi +2 laps Retirements: Rob Austin RAR Audi 11 laps Warren Scott BMR Vauxhall 5 laps Glynn Geddie UA Toyota 5 laps Marc Hynes MG 0 laps