BMW driver D'Aste, who started 17th, inherited the win after Fabrizio Giovanardi, Gabriele Tarquini, Antonio Garcia, and Dirk Muller were all involved in a bizarre accident through the Bus Stop chicane on the last lap.
Garcia tapped Tarquini while approaching the Bus Stop, which pitched the Alfa Romeo driver into Dirk Muller's BMW. Muller then slid round and back into Tarquini, who in turn again hit Garcia. The trio then lost control and spun simultaneously into the chicane.
Giovanardi, who led into the corner and had looked comfortable for the win, failed to make it though the exit cleanly, having to avoid the spinning Tarquini in front of him.
All this meant that D'Aste, who had his own share of last-lap drama, having gone off on the wet grass at top speed at Les Combes, was able to inherit a remarkable victory.
Giovanardi, who had led the entire race until the crash, managed to struggle home second ahead of Tom Coronel and Augusto Farfus Jr. Muller scrambled home fifth with Garcia eighth. Tarquini retired.
D'Aste was stunned at the victory. He said: "It is not often an independent driver wins a World Championship event. This was a big weekend for us, we had done lots of work after BMW gave us a new engine."
The controversial last lap accident wasn't the only one in the race, which had suffered a wet downpour moments before the start.
The leading cars had been so close on that final lap because of a safety car period brought out for an accident between Thomas Klenke and Jordi Gene at the bus stop. Nicola Larini nudged Klenke into a spin on the run down to the chicane, pushing the Focus driver onto the wet grass. Unable to slow down, he smashed into the innocent Gene at the chicane spilling debris over the track.
Race one leaders Dirk Muller and Andy Priaulx touched on the run down to Eau Rouge just after the start. The collision pitched Dirk Muller into Farfus Jr. The pair had a frightening spin infront of the pack at Eau Rouge however, they both managed to avoid the field. However too much damage was done to Priaulx's suspension in the accident to continue.
Pos Driver Make Time
1. Stefano D'Aste BMW 320i 27:46.760
2. Fabrizio Giovanardi Alfa Romeo 156 + 2.997
3. Tom Coronel Seat Toledo Cupra + 4.368
4. Augusto Farfus Jr. Alfa Romeo 156 + 4.920
5. Dirk Muller BMW 320i + 7.047
6. Alain Menu Chevrolet Lacetti + 10.616
7. James Thompson Alfa Romeo 156 + 12.804
8. Antonio Garcia BMW 320i + 13.066
9. Marc Hennerici BMW 320i + 13.575
10. Peter Terting SEAT Toledo Cupra + 17.203
11. Robert Huff Chevrolet Lacetti + 17.626
12. Carl Rosenblad BMW 320i + 18.205
13. Adam Lacko BMW 320i + 18.631
14. Jason Plato SEAT Toledo Cupra + 20.594
15. Giuseppe Ciro BMW 320i + 21.702
16. Jorg Muller BMW 320i + 46.974
17. Gabriele Tarquini Alfa Romeo 156 + 1 Lap
18. Nicola Larini Chevrolet Lacetti + 1 Lap
Driver Make On Lap
Roberto Colciago Honda Accord Euro R 4
Jordi Gene SEAT Toledo Cupra 3
Thomas Klenke Ford Focus 3
Valle Makela Seat Toledo Cupra 1
Rickard Rydell SEAT Toledo Cupra 0
Soheil Ayari Peugeot 407 0
Andy Priaulx BMW 320i 0
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