Officially third home in the 15th running of the GP in the F3 class was the pacesetter from the first leg, Brazilian Enrique Bernoldi in a Promotecme Dallara Renault-RS, who was only 1.904 seconds off the pace.

The lead changed several times between the top three in a thrilling climax to a great weekend of racing blessed with clear skies and sunshine.

A euphoric Dumbreck described the result as twice as good as any other victory he had achieved.

'The pit crew were cheering when I crossed the line but I still wasn't convinced I'd won. It wasn't until I returned to the pits that I was sure of the result,' the 25-year-old said.

Twenty-year-old Mauricio was remarkably upbeat for a driver beaten by such a tiny margin.

'It was a good race - really exciting. My last lap was my quickest and I almost crashed, I gave it everything,' he said.

The race was spiced with the unexpected even before it had begun when track officials ordered a rolling start after oil spilt on the starting grid following an earlier race rendered a standing start too dangerous.

Second on the grid, Bernoldi got the best of the rolling start to claim pole-sitter Robert Lechner of Germany under brakes into the 90-degree, right-hand Lisboa Bend.

Bernoldi drove a controlled race in front and was just under a second clear of Lechner's GM-DSF Team Dallara Opel-Spiess after the first lap, with Dumbreck in third slot.

Bernoldi continued to dictate the pace until lap six when Dumbreck uncorked a sizzling time of two minutes and 16.890 seconds, a time which dipped below Dutchman Tom Coronel's lap record of 2:15.950 set last year.

Dumbreck eclipsed it again on lap 13 with a sizzling time of 2:15.727. But it wasn't sufficient to dislodge the leading pair.

At the halfway point, ice-cool Bernoldi had increased his buffer to 2.392 seconds, with Dumbreck 3.7 seconds adrift. Mauricio was down in fifth place, 8.5 seconds behind.

Hometown hope Andre Couto filled fifth place in his Prema Powerteam Dallara Opel-Spiess, eight seconds adrift.

The race seemed to be a battle between the top three, but nobody told 19-year-old Mauricio that when the second leg began via the conventional standing start.

He showed blistering speed off the mark and led on the track for the entire second leg, only to fall so agonisingly short in the overall equation.

Couto's hopes of victory disappeared only seconds into the second leg when he misjudged his entry into Lisboa Bend and shot down the runoff road.

Bernoldi was caught napping on the starting grid and was shunted back to fifth on the road, even though he continued to lead on aggregate.

'It was not a very good start and I wasn't very fast in the straight - I could do nothing to stop them going past me,' Bernoldi explained.

To his credit, he had climbed back to third place on the road in the second leg by the eighth lap. But the damage had been done as Mauricio claimed the overall lead four laps into the second leg.

Dumbreck made his move on lap seven when he lowered his lap record to 2:15.545 and on the next lap unleashed a 2:15.455.

Bernoldi could see his race falling apart but he still produced a record of his own with five laps remaining - 2:14.978. But a lap later, Dumbreck swept into second place overall and began to inextricably haul in Mauricio.

Bernoldi wasn't finished, with yet another lap record, 2:14.871, before a mistake two laps from home ended his challenge. Mauricio held a slender lead of around 3/10ths of a second when Dumbreck continued his record-breaking blitz with a time of 2:14.71 and on lap 28 and grabbed the overall lead.