There was a disappointing end to the FIA GT1 World Championship for David Brabham and Jamie Campbell-Walter as their Sumo Power GT entry suffered a dramatic DNF in the final round in Argentina.

While team-mates Enrique Bernoldi and Nick Catsburg took the #20 sister car to a pair of hard-fought fourth-place finishes, Brabham and Campbell-Walter's #21 entry managed seventh in race one before becoming caught up in a massive start-line shunt that played out ahead of the Australian in the finale.

Following a season of mixed fortunes, the Sumo Power team went to Argentina with the hope of scoring good results at a circuit that was likely to extol the virtues of the Nissan GT-R. Built around a lake that lies in the centre of an extinct volcano, the track is totally unique, with fast and wide sections, coupled with the undulating topography and walls that surround the whole of the 6.22km circuit, making it as demanding as it is picturesque.

Because it is a public road for most of the year, the surface of the track is not as clean as a purpose-built race circuit but, even so, the two Sumo Power entries performed well during Friday's free practice and pre-qualifying sessions and continued that theme into Saturday morning's qualifying.

Both cars made it through to Q3 and the shoot-out for the top-eight positions, with the #21 car starting the first race from third on the grid, and all four drivers saying their machines had never felt better.

With a dusty left-hand side of the track to contend with, Campbell-Walter could not get traction from the rolling start and dropped to fifth, allowing Catsburg's #20 car to slip past into fourth. The two GT-Rs continued to run line astern for several laps, building up for an attack on the Lamborghini.

When the car ahead of him braked earlier than expected, Catsburg locked up on the approach to the second chicane. This let Campbell-Walter past and, as the race progressed, it was clear that the Scot was faster than the Lamborghini and pushing for position as the compulsory pit-stops approached.

The #21 car was first to pit but, whilst trying to gain a place by putting in a typically ultra-fast stop, a nut became jammed as the crew tried to replace the right-rear wheel. Consequently, the time spent in the pits was twice what it should have been and Brabham emerged from the pits in ninth place.

The Australian was loving the track and the way his GT-R was performing and went on to set times that equalled - or in some cases bettered - that of the race leaders. The veteran's pace was such that he was able to climb two positions during his stint, which meant he crossed the line in seventh.

With all four drivers confirming that the GT-Rs were potential race winners, hopes were high for race two but, as the pole-sitting Corvette approached the lights for the rolling start, it slowed, bunching up the charging pack behind it.

Seeing a gap in front of him, Bernoldi stuck the nose of his GT-R between the two front-row sitters, only to be hit from behind by a Lamborghini. The knock-on effect meant that he nudged someone else who nudged someone else and, in the next few seconds, there were cars spinning and bits of carbon fibre everywhere.

Although Bernoldi suffered a puncture in the mayhem, there was worse news for Brabham, who found he had nowhere to go, resulting in damage to the front of his GT-R which left it unable to continue.

The incident brought out the safety car, and it was 25 minutes and six laps at restricted speed before the track became clear and racing could resume but, for Brabham and Campbell-Walter, the season was already over.

"What can you say about the second race, other than it was such a shame, as I think we were in for a top-three," the Australian lamented, " It's particularly frustrating as the problem with the wheel nut in the first race cost us 22 seconds and, as it turned out, we crossed the line 22 seconds behind the winner!"

Despite his disappointment, Brabham was full of praise for both the Potrero de los Funes circuit and the Sumo Power GT team.

"I really love this circuit," he enthused, "It's a cross between Le Mans and Bathurst and the GT-R was mega around it.

"The boys gave us such a good car this weekend that every lap of my stint I was able to drive flat-out. It was like 12 laps of qualifying! I've really enjoyed working with Jamie and the team this season and my thanks go to everyone involved."

The action-packed end to Sumo Power GT's second season in the FIA GT1 World Championship saw Brabham and Campbell-Walter finish tenth in the overall standings, whilst the team claimed fifth overall.

"What a weekend!" team principal Andy Barnes, "It's been a roller-coaster. We were determined to finish in spectacular style and it's clear everyone was aiming high. We gave it our all.

"Even without podiums to reward the team work and the performance of our drivers, we end the season in good spirits after a troublesome but thoroughly enjoyable year. We never gave up and kept pushing until the very end, which is a Sumo Power philosophy."